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The Journal of Agricultural and Applied Economicsis an open access forum for creative and scholarly work in agricultural…. BJHS Themes is a new, fully open access, peer-reviewed journal for the history of science. It publishes annual thematic…. Free Access to Volumes JBCA is the only journal devoted exclusively to benefit-cost analysis, the leading evidence-based…. The Nagoya Mathematical Journal is published quarterly. Since its formation in by a group led by Tadashi Nakayama,…. Design Science is an international open access journal publishing original quantitative and qualitative research….
The Mathematical Gazette is one of the leading journals in its field, publishing important and influential articles…. The Canadian Journal of Neurological Sciences is the official publication of the four member societies of the Canadian…. Published on behalf of the Paleontological Society Impact Factor: Business Ethics Quarterly BEQ is a peer-reviewed scholarly journal which publishes theoretical and empirical research….
Developing Practical Wireless Applications will explore this question and, in doing so, will illustrate many of the wireless technologies currently available whilst. Developing Practical Wireless Applications discusses a broad range of wireless technologies, each of which uniquely imparts its own capabilities and features.
The aim of the journal…. Global Sustainability is a new Open Access journal dedicated to supporting the rapidly expanding area of global sustainability…. Cambridge University Press to publish Political Analysis from Political Analysis publishes cutting-edge research…. Business and Politics has established itself as the premier journal for cutting-edge research on the relationship…. The Australasian Journal of Special and Inclusive Education publishes articles for a readership professionally engaged….
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Home Academic Computer science Software engineering and development. Add to cart Add to wishlist Looking for an inspection copy? Log in to review. How do you rate this item? Reviews must contain at least 12 words about the product. Table of Contents Part I. The Journal of Agricultural Science The Journal of Agricultural Science publishes papers concerned with the advance of agriculture and the use of land….
Journal of Symbolic Logic The Journal of Symbolic Logic publishes research in mathematical logic and its applications of the highest quality. Wireless Power Transfer Launched in , Wireless Power Transfer is the first journal dedicated to publishing original research and industrial…. Journal of Policy History The Journal of Policy History is an interdisciplinary journal concerned with the application of historical perspectives…. Australasian Journal of Special Education The Australasian Journal of Special Education publishes articles for a readership professionally engaged or interested….
Animal Health Research Reviews Animal Health Research Reviews provides an international forum for the publication of reviews and commentaries on…. Visual Neuroscience Impact Factor: Phonology Phonology, published three times a year, is the only journal devoted to all aspects of the discipline, and provides…. Modern Asian Studies Modern Asian Studies promotes original, innovative and rigorous research on the history, sociology, economics and….
International Journal of Disability Management International Journal of Disability Management publishes research findings in areas including prevention of injury….
Microscopy and Microanalysis Microscopy and Microanalysis publishes original research papers in the fields of microscopy, imaging, and compositional…. Management and Organization Review Now published by Cambridge. Journal of Dairy Research Journal of Dairy Research publishes original scientific research on all aspects of mammary biology and dairy science….
Australian Journal of Environmental Education An internationally refereed journal which publishes papers and reports on all aspects of environmental education. Children Australia Children Australia links policy, research and practice related to children, young people and their families across…. Queensland Review Queensland Review is a multi-disciplinary journal of Australian Studies which focusses on the history, literature,…. Advances in Animal Biosciences Advances in Animal Biosciences is an associated publication to the journal animal. Radioprotection New to CJO in Radioprotection publishes articles on all aspects of radiological protection, including non-ionising….
History in Africa History In Africa focuses on historiographical and methodological concerns and publishes textual analysis and criticism,…. New Surveys in the Classics The New Surveys in the Classics are a series of short books dedicated to key themes and concepts in the classical…. Iraq Iraq is an academic periodical founded in and appearing annually. Journal of Law and Religion The Journal of Law and Religion publishes cutting-edge research on religion, human rights, and religious freedom;…. Network Science Network Science is a new journal for a new discipline - one using the network paradigm, focusing on actors and relational….
Journal of Agricultural and Applied Economics The Journal of Agricultural and Applied Economicsis an open access forum for creative and scholarly work in agricultural…. Design Science Design Science is an international open access journal publishing original quantitative and qualitative research…. The Mathematical Gazette The Mathematical Gazette is one of the leading journals in its field, publishing important and influential articles….
Global Sustainability Global Sustainability is a new Open Access journal dedicated to supporting the rapidly expanding area of global sustainability…. One common and, often, harmonious driving issue that many manufacturers discuss is that of interoperability, that is, where one manufacturers product successfully works with another manufacturers. Does a company really need to implement a wireless infrastructure? Undeniably, these fundamental factors form part of the decision-making process.
We have already acknowledged that the financial aspect of implementing such an infrastructure is nowadays significantly cost effective, as the availability of wireless-enabled products is widespread and, naturally, the cost is proportional to the size of a company. We have witnessed many notebook and desktop manufacturers offering integral wireless solutions that are ready to go and require minimal configuration. Some companies may choose to purchase a PCCard- or USB-based product to metamorphosize their standalone computers into the new wireless generation. Again, these products are commonplace, but who will support this new infrastructure?
Many companies specialize in the implementation and deployment of such infrastructures and are readily available to assist. However, consideration of this kind of outsourcing needs to be added to the overall projected cost of deploying and implementing such an infrastructure. Nowadays, a significant number of companies have their own internal IT departments where several administrators may manage wireless deployment and subsequent maintenance.
This approach is a practical solution and will help reduce the overall financial outlay within a company. However, consideration needs to be given to possible retraining within the related IT department. Moreover, what about the practical usability and user friendliness of the many wireless products on offer: Will they find the educational aspect of adopting a new wireless product a chore? To many of us, there is a sense of initial eagerness, coupled with frivolity as we unwrap the product, put aside the packaging; scan the accompanying software CD and observe the product in 3D in our hand.
With this in mind, we need to ask ourselves: Were we already comfortable with using the snake-like cables which, initially, seemed like a black art to master; or do we find that the introduction of a technology such as Bluetooth, with its abracadabra-like magic wand, has wirelessly tapped the top of our notebook three times wishing the cables away? Where is the Original Thought? It is clearly evident that most of us companies and individuals alike have formulated our own conclusions regarding the positive and negative aspects of new wireless technology.
Making Sense of Wireless Technology 7 We talk of configuration issues and how difficult it is moving from one network to another. But, whether we choose to accept it or not, manufacturers and their marketers are committed to seducing us all into adopting and embracing its alleged benefits. This leads to another important question: We often witness an increasing number of pop bands covering old classics and reinventing them as their own. Are manufacturers similarly guilty of a lack of originality with their wireless products?
Where is the original thought? We find ourselves replacing infrared in a remote control with Bluetooth or ZigBee as another new technology, accompanied with yet another marketing spin: After all, developing the right product for the right kind of market will undoubtedly create a new way of thinking for consumers and, in turn, they will become our judge and executioner regarding its success or failure.
But oddly enough, most manufacturers choose to ensure that a product released on the market has satisfied the demographic; they are no longer taking risks — they need a sure thing. With a degree of educated certainty and no matter how much money you invest into a new product, ultimately the consumer will decide. Should we therefore rely on consumerism and its behavior to bias our sense of proportion and reality? A New Way of Thinking Perhaps the marketers that exploited the intricacies of the technologies by associating the without wires factor with the innate capabilities of wireless have brought about this radical change in perception, or perhaps we, as consumers, have created the transition of association ourselves through a need to condense our growing fascination with mobility, freedom and time conservation into a single word.
Most likely the change was brought about through a combination of the two, but it marks a clear boundary between wide-area and personal-area generations of wireless technologies upon which the latter this book is primarily based. This change has inescapably brought about a new way of thinking. Chapter 1 8 Developing Practical Wireless Applications In making sense of wireless technology, we have posed positive and negative questions to ourselves and internally wrangled with the financial, usability, security and practicality factors. Wireless technology has become an effective communications tool.
Communication is the heart and soul of every business and while we remain connected we continue doing business. It has also enabled us to communicate over great distances. But just a moment! Surely we escape to a restaurant or to the beach with an aim to banish the constraints of the working day?
Personal-area wireless technologies have entered into certain aspects of our living and working lives. Nowadays, consumers are more aware of new wireless technology and, as such, have moved away from the traditional notion of wireless. The influence of wireless depends upon numerous scenarios, coupled with varying types of exposure and environmental facets. End-users and companies lean towards certain business models which, in turn, justify their purchase or non-purchase of wireless-enabled products.
These business models may have an attached financial, practical, usability or security factor, which is channeled into a decision-making process. We need to be clear in our own minds why we have and are using wireless technology. What we are led to believe about wireless technology is based on the concept of an environment that bestows ease-of-use, seamless operation and transparency. There is a striking cost—benefit in implementing wireless, as the availability of wireless products is now very widespread.
Standards bodies actively assure us that security concerns are a thing of the past. A driving issue that many manufacturers discuss is that of interoperability. Configuring some wireless networks can be cumbersome to set-up. Fundamental factors such as cost form part of the decision-making process. The cost of setting up a wireless infrastructure is proportional to the size of your company. Many manufacturers integrate wireless within their notebooks and desktops.
Some companies may outsource their implementation and deployment of a wireless infrastructure. Outsourcing of this nature should be added to the overall cost. A significant number of companies have their own internal IT departments where several administrators may manage the wireless infrastructure. Ordinary users are also faced with practical usability and user friendliness factors when deciding to purchase a new product. As individuals we will have already formulated our own conclusions regarding the positive or negative aspects of new wireless technology. The adoption of new wireless technology has inescapably brought about a new way of thinking.
Are manufacturers creating wireless products unnecessarily? Developing the right product for the right kind of market will undoubtedly create a new way of thinking for consumers. Undoubtedly, financial constraints will diminish; usability will become simpler and adoption will become wider. Chapter 1 2 Understanding the Wireless Audience This chapter has its roots in consumer psychology for a very good reason. Our primary objective in this chapter is to shine some light on the consumer psyche and, perhaps more importantly, to move this light around so as to illuminate and expose the deep crevasses within see Figure 2.
We will then be more successful in attempting to categorize consumers by age, motivation, income and usage scenarios. We try to find purpose and direction for all areas of our lives. From setting up a home to running a business, we all internalize the procedures that govern our choices and behavior and place these into clearly defined mental boxes, formed through a combination of past experience and the practical opportunities that face us.
The problem with these boxes is that they are, all too often, walls without doors. Confining us into a set of expectations and behavior patterns that stretch our limitations as partners, parents and employees and becoming more like prisons than the ordered sanctuaries we had formed them to be. Utilizing wireless technology allows us to finally place doors into our walls and merge internalized boundaries into one another as we are introduced to new levels of portability and freedom, both at home and in the workplace.
For many consumers, the concept of this kind of wireless liberty is a heady revelation, yet, amazingly, it is one that marketers have only recently begun to fully exploit. We were blasted with numerous messages, telling us how new wireless technology worked and hyping its potential far beyond its initial capabilities, in a way that most consumers found intimidating and non-supportive of their life-style and expectations.
Support is the key word here. To put a wireless product into a clear usage scenario for the consumer, it needs to be seen to provide a support structure for a particular aspect of their lives. A good example here would be the illustration of a mother sending and receiving emails from her Personal Digital Assistant PDA outside the school where she has just dropped off her children.
This image combines the twin aspects of family and work responsibilities and allows the consumer to psychologically bridge the gap between Chapter 2 12 Developing Practical Wireless Applications the two through wireless functionality. With this in mind, when developing a new wireless application, we can see that defining its intended support attributes within clear usage scenarios is just as important as choosing the right wireless technology for the intended end product. In fact, one aspect will undoubtedly impact upon the success of the other.
Because of its innate attributes of mobility and freedom, the market for wireless products is extensive and spans from the rapidly evolving mobile youth market to the protection and security provided to the elderly through wireless home monitoring systems. Currently the biggest slice of the wireless spectrum is that of the mid-generation twenty-five to forty year olds, where work and home responsibilities make time a precious commodity.
According to consumer watchers TrendWatch TrendWatching. Clever wireless manufacturers have responded to this need and are continually working to position a new religion of hotspot worship see Figure 2. A hotspot provides the ability for users with a notebook computer or PDA to access the Internet or the office Intranet through a secure wireless connection.
The WiFi Alliance a non-profit international association formed in offers a comprehensive list of hotspot locations through their WiFi Zone program. Understanding the Wireless Audience 13 And, when looking beyond our virtual workspace to other dimensions of our lives, particularly those of entertainment and education, the same holds true.
The freedom afforded to the wireless executive extends out from the workforce to other areas of life such as entertainment and education. Today, our kitchens can become classrooms and our laundry rooms libraries. Some worry that old-fashioned family values are being swept away by the wireless tidal radio wave, whilst others revel in the freedom afforded to their families and embrace the diversity of living and working without wires. Categorizing the Wireless Audience In order to assist in both the initial development planning procedures and long-term market positioning of new wireless products, we need to clearly segment the market into distinct consumer groups, each assessed by motivation to purchase and typical usage patterns.
As such, Table 2. The Diffusion of Wireless Innovation This term, diffusion of innovation, is particularly relevant when building an understanding of the new wireless audience, as it refers to the tendency for new types of products, practices or ideas to increase among people. Early adopters are crucial to a Table 2. Youth Market between 12 and 24 Years Description Motivation Peer cohesion and a sense of belonging, individuality from other groups in terms of style and usage models with an emphasis on entertainment and peer-to-peer communication.
Identifiable Product Cell phones with interchangeable covers to allow for personalization between user groups, Short Message Services SMSs and Multimedia Messaging Services MMSs applications, integrated digital cameras, third generation 3G video and gaming capability, ring tone bolt-ons.
Typical Usage Pay as you go cellular phone accounts low budgets with younger Group Ones. High levels of SMSing or texting and inbuilt gaming facilities. Mid Generation Executives 24 to 55 Years Description Motivation Career tracking, time control, the integration of work and pleasure, support systems career and home , keeping up with technological advances, prestigious individuality. Identifiable Product WiFi integrated laptop or PDA, enabling hotspot access to the Internet and easy synchronization of data between home and office.
Bluetooth-enabled cell phone to access the Internet or office when no hotspot is available. Income Factors Mid to high levels of expendable income Mid to high levels of income Table 2. Identifiable Product Bluetooth-enabled cell phone and headset. Typical Usage Communicating with work, home and family — usually on a pay as you go or economy fixed monthly package. Income Factors Low levels of expendable income Low to mid levels of income Table 2. Identifiable Product Wireless health monitor necklace and wall-mounted transceiver. Contact will be made via the transceiver to check on the status of the wearer whilst help is sent.
Wireless technology is a dynamically continuous innovation due to the fact that it is constantly evolving and adapting to new types of application and usage models. Visionaries, engineers, managers and investors need to ensure that the evolution of their wireless applications is possible in a way that requires little or no re-education on the part of the user.
Alongside the evolved practicalities of new wireless applications, many successful wireless devices have been developed and initially marketed through the creation of consumer needs. Factors such as life-style models, as depicted in our previous categorizations see Table 2. Early adopters then ensure that these life-style model needs are further reinforced within the target market, resulting in an increased diffusion of innovation. Cultural Economic Effects on Product Pricing The majority of wireless pricing research has been carried out on US consumers, which raises the potential issue of oversimplification in certain global-economic areas of theory.
Evidence, however, exists of a strong correlation between quality and price in the mind of the UK and Japanese consumers whilst, in less developed countries, price does not necessarily have a strong relationship with perceived product longevity or quality of build and, accordingly, far less consumer brand loyalty exists. In the case of mobile application developers, building good relationships with carriers is key to ensuring that cultural needs and variances are built into new wireless applications. For example, gaming applications based upon the latest movie themes can be more easily managed when carriers are able to play a part in accurately promoting launch dates in accordance with appropriate media tie-ins and cinema release dates.
Chapter 2 16 Developing Practical Wireless Applications This process is of particular value to new developers, whose application adoption may be assisted by carrier association. In the US the carrier relationship is considered to be particularly valuable and this holds true in other countries as well. In the UK and the rest of Europe, however, distribution has a slightly different emphasis and much occurs through aggregators or portal sites. Trends are already beginning to show themselves in terms of wireless application take-up and we can further build upon these demographics to make intelligent predictions about where future development paths might lead us.
Consumers can be categorized into distinguished groups with attributes such as motivation, age, income and usage scenarios. As consumers, we try to find purpose and direction for all areas of our lives; from setting up our home to running a business. We all internalize the procedures that govern our choices and behavior into clearly defined boxes, formed through a combination of past experience and the practical opportunities that face us. This confinement turns our boxes into prisons rather than the ordered sanctuaries we had formed them to be.
Wireless technology offers us an extraordinary liberty. Utilizing wireless technology initially activates the process of placing doors into our walls, where over time these walls begin to diminish. Marketers have only recently begun to fully exploit the real benefit of this wireless liberty.
More and more wireless products are becoming supportive of our everyday needs. Nowadays, marketers are using clearer messages in their marketing. When developing a new wireless application, we can see that defining its intended support attributes within clear usage scenarios is just as important as choosing the right wireless technology for the intended end product. The market for wireless products is extensive and spans from the rapidly evolving mobile youth market to the protection and security provided to the elderly through wireless home monitoring systems.
Wireless manufacturers are continually responding to the need of the consumer. And, when looking beyond our virtual workspace to other dimensions of our lives, particularly those of entertainment and education, the same holds true. Today, our kitchens can become classrooms and our laundry room libraries. Some worry that old-fashioned family values are being swept away by the wireless tidal radio wave, whilst others revel in the freedom afforded to their families and embrace the new diversity of living and working without wires.
We need to clearly segment the market into distinct consumer groups, each assessed by motivation to purchase and typical usage patterns. Diffusion of innovation is particularly relevant to understanding the new wireless audience, as it refers to the tendency for new types of products, practices or ideas. These early adopters will generate group interest among other social and peer groups, resulting in a well-received product that is embraced and accepted by a wider range of users.
Early adopters also ensure that life-style model needs are further reinforced within the target market. Wireless technology is a dynamically continuous innovation due to the fact that it is constantly evolving and adapting. Manufacturers should keep re-education to a minimum. Differences in economic culture have a dramatic impact upon pricing and promotion. We do need to be able to take what we already know about the evolution of wireless and to combine this knowledge with educated intuition about the future.
In establishing a new era of wireless technology enabling personal freedom and mobility has both distinctive parallels and contradictions to the older, more established wireless technologies. We should not forget that wireless technology emerged in the late 19th century. Both wide-area networks WANs and personal-area networks PANs share a common radio medium in which data is transferred between electronic devices, but it is a combination of consumer perception and usage scenarios that distinguishes them. As we move forward in this chapter, we will clarify the distinction that can be made between wide- and personal-area wireless, alongside an in-depth discussion of the technologies that underlie most cellular-centric products.
Additionally, we will consider the perception that most of us enjoy when we come into contact with wide- or personal-area technologies. We will discover that these technologies are, indeed, complementary and together provide some powerful applications.
It is covered in the chapter as a means of providing a holistic perspective of the available technologies, whilst not detracting from our primary focus. Personal-area The more established or wide-area technologies, such as cellular and satellite, are tried and trusted communication technologies that have been around for many years.
Typically, in this context the user has been able to establish a level of familiarity where the wireless capability is no longer the perceived application. Incidentally, he also brought about a standardization that enabled the international maritime services to adopt his technology, as an effective communications method for naval vessels at sea. Similarly, telecommunications are prevalent in all sorts of infrastructures and in Figure 3. Nowadays, new wireless technology focuses primarily on personal-area communications, with the introduction of a new range of wireless-enabled applications that, in turn, define a greater sense of personal mobility and freedom that uniquely captures the personal-area technology era.
Personal-area technology enables users to create their own personal communications environment, which may comprise a notebook wirelessly connected to a network and a cell phone that utilizes a Bluetooth-enabled headset. In the latter example we can see how wide- and personal-area communications Figure 3.
Wide-area and Personal-area Communications 21 Figure 3. One clear distinction between these technology types is the complacency that a user establishes with a product over a period of time; we touched upon this earlier. This familiarity breeds complacency towards the intended wireless device. In other words, do we perceive a cell phone as a wireless-enabled product? Indeed, the cordless Figure 3. In this example, a user has a Bluetooth-enabled headset along with a cellular phone, notebook and PDA. These PANs are capable of doing so as a result of the wide-area communications network, which may be supported by a dial-up connection.
It may be apparent to some users that a cell phone and a cordless telephone operate via a wireless medium. Nevertheless, some users and arguably the majority of them may only perceive the intended telephone functionality, rather than its inherent wireless capability. This essentially forms the subtle basis in our consumer perception and usage scenarios; it is this observation that distinguishes wide-area and personal-area wireless technologies.
There is nothing unfavorable with this concept, but this book primarily discusses the newer personal-area wireless technologies that afford a new generation of mobility and freedom. It is after all the focus of marketers to drive the new generation of Wide-area and Personal-area Communications 23 wireless-enabled products, and Developing Practical Wireless Applications explores in some detail the existing and emerging new wireless technologies, coupled with the myriad of applications that occupy and impress upon our personal and working environments.
In the following sections we appraise the generations of more established wireless technologies and it will naturally provide a complete picture of the historical generation of wide- and personal-area, whilst molding a comparable impression of the overlap created between them. It is becoming more evident that manufacturers integrate new wireless technology into cellular phones, notebooks and so on, resulting in the overlap of wide-area and personal-area communications see Figure 3. It is this overlap that bestows the mobility and freedom characteristics of our personal and working environments.
Generations of Wireless Technology Undoubtedly, many of us have witnessed the emergence of generations of wide-area technologies each depicting the advancement of applications and digital capability. Regularly we read in the technology news, the relentless press releases announcing faster and better applications that now rely on 3G technology more about this later. Perhaps the label of old seems somewhat inappropriate, as the more established generations of the wide-area era are growing at a phenomenal rate.
The depiction of wide-area communications helps us understand clearly where the respective technologies lie within the realm of personal-area emerging technologies, as we have conceptualized in Figure 3. First Generation 1G First generation or 1G cellular telecommunications were only capable of supporting voice traffic. Understanding how FDMA works FDMA offers a radio spectrum that is divided into channels, where typically each channel is 30kHz; there is also a separate control channel, which is used to manage and coordinate voice channel assignment.
When a cellular phone initiates a call, a frequency channel is reserved for the duration of that call; frequency modulation is then used to modulate voice data within the reserved frequency band. Wide-area and Personal-area Communications 25 In this scenario the allocation or reservation of a channel remember there are two 30kHz channels is assigned uniquely to a user at any one time.
Naturally, this approach limits the available number of users that can make use of the cellular service through a base station. A base station is a permanent erected structure that houses a transceiver and is connected to the wider telephony infrastructure, in turn, enabling the ability for a cellular user to initiate and receive calls, whilst being mobile. This system has now been largely replaced with the digital generation of cellular telecommunications. Indeed, with the emergence of second generation 2G technology, we experience a broader capability, accompanied with increased reliability and security, which now includes the ability to transmit and receive data more effectively.
Comparing analog and digital communications It seems an endless battle of analog versus digital with the latter dominating most wireless-enabled products and, of course, most cellular-centric technologies. It is perhaps worth pausing for a moment to consider the differences and advantages that digital has over analog communication systems. An analog system lends itself naturally to the characteristics of the human voice. The signal witnessed by such a system is that of a sine wave, as shown in Figure 3. Unfortunately, this type of communication is prone to interference and, as such, loss of communication occurs; this sine wave represents the original format of the data being transmitted.
In this particular instance, communication is highly susceptible to noise, in turn, causing unreliability users of an analog voice-enabled system would experience noise or hissing during the conversation. An analog system also occupies a lot more spectrum, compared with its digital counterpart. The bandwidth remains in use during the call and naturally this occupancy reduces the number of users who are able to use the service. Moreover, analog communication generally remains open to eavesdroppers, as we illustrated earlier in our introduction of 1G technology.
Since the analog data is transmitted in its original form various pieces of equipment, such as scanners, are available enabling individuals to eavesdrop on telephone conversations eavesdropping is not limited to voice communication, data transmitted in this format is also prone to security risks. Additionally, analog systems consume greater power than its digital counterpart, making digital systems much more power consumption friendly.
Unlike analog, digital communication transmits its data using a series of pulses, as shown in Figure 3. The digital wave form has two states: This representation is typical of all digital-enabled equipment. During digital transmission, a radio receiver can easily distinguish between the series of pulses high and low from any background interference, such as noise.
Reliability is ensured using various types of encoding schemes that is added to the data transmission; if the message is not received then the transmitter will retransmit it. Using a variety of encryption methods, securing the data before transmission overcomes Figure 3. Wide-area and Personal-area Communications 27 potential eavesdropping. Typically, two devices will agree upon an encryption scheme and the transmitter will decrypt it accordingly using the agreed parameters.
Additionally, numerous schemes are available enabling cellular services to increase the available bandwidth; we now discuss this further in the following section. Second Generation 2G , 2. Incidentally, a large part of the North American cellular coverage is still operated using AMPS the analog system, which we introduced earlier and, as such, US operators are actively making a shift to newer digital technologies, which we will discuss later on. The basic premise is the same as an analog system, in that the available frequencies that are open to an analog system are also available to a digital system.
The distinction between them is that the digital system uses the frequencies in a different way, more specifically, a channel is divided into time slots, as we illustrate in Figure 3. This method is not unique to cellular communications either; similar techniques can be found in networking technologies, such as Ethernet These three variants are incompatible and have implemented the TDMA scheme in different ways. Chapter 3 28 Developing Practical Wireless Applications As a result they are competitive solutions in delivering cellular telecommunication services for its consumers.
It takes the existing 30kHz channel, which would be allocated to a single user for an FDMA topology, and divides it into three slots; effectively this division creates three further channels. Now multiply this over the available spectrum and you have increased the service capacity by a factor of three; however, newer TDMA systems increase this capacity by a factor of six by employing better compression techniques; in other words, compressing more data into one time slot. One of many advantages for using TDMA is its digital premise and, of course, its ability to support data-centric communications.
Similarly, voice quality is increased and, as a result becomes much more secure. Other factors such as power consumption and cost effective transceivers make it an attractive option for cellular phone manufacturers. TDMA digitizes the voice traffic into a packet, this is then placed into a time slot measured in terms of milliseconds onto a channel. For each subsequent packet a different channel is allocated, as we have already illustrated in Figure 3. The whole process then becomes cyclic where old time slots are reused.
It is these standards that govern telecommunication functionality, features and capabilities within the US and, of course, other parts of the world where it has also been deployed through the two systems known as AMPS and D-AMPS. In utilizing this scheme, network operators were able to increase the number of users that could use their service by up to six times, as compared with the original analog AMPS service.
It is also worth Wide-area and Personal-area Communications 29 commenting that with 2. Currently, the ability to text enables the user to send a short text message, typically characters per message, to one or more users. Some network operators provide the ability to split large text messages into two SMSs. For example, if a text message comprises characters the first will be sent as one text message, followed by the remainder characters as another text message.
Similarly, MMS provides the ability to send text messages with an increased capability to send larger text messages without the need to split them over one or more SMSs , but the user now has the ability to attach images, pictures and audio. Multimedia enabled cellular phones are increasingly popular with the youth market; integral digital camera capability and live video images are prevalent in the UK, Europe and Asia. It is the demand for these types of applications that are driving increased data rates, which is ultimately leading to the promised third generation technology.
Despite the fact that PDC is only available to Japanese consumers it still remains the second largest cellular standard in operation. The success and popularity of PDC in Japan can be credited, in part, to i-Mode, an Internet-based service providing capabilities such as web browsing and email. WAP was developed by a consortium of companies Phone.
Its aim was to establish a common platform to facilitate the presence of Internet-based applications on cellular phones. A strong argument to its development was to alleviate confusion for the consumer, since there are numerous telephony standards for delivering cellular telecommunications, namely D-AMPS, GSM, PDC and so on.
It would be natural to assume that a crossover, from PCs to cellular phones and its web-based applications would begin to emerge. However, with the intrinsic small screen area it was all too often cumbersome and awkward to navigate. Internet Service Providers ISPs had to rewrite areas of their website to enable users of WAP-enabled phones to view web pages and, as such, a large business community had to invest effort and expense in realizing the WAP dream. Chapter 3 30 Developing Practical Wireless Applications i-Mode on the other hand established over six million subscribers circa by operating a technology that was not compatible with WAP.
It has been deployed throughout Europe, as a de facto European standard, and the rest of the world, to include South America, Australia, Asia, the Middle East and Africa. At the time of writing, current figures estimate almost two billion consumers spaced over approximately countries use GSM as their cellular service. Additionally, it was the first cellular system to specify digital capability and define network infrastructures. With the introduction of GSM as a de facto European standard, operating at MHz and MHz whereas North America utilizes the MHz band , we have begun to establish a globally reliable and effective system for telecommunications.
With the continued growth and demand for better applications, that is, applications beyond voice capability, GSM has evolved accordingly. A fundamental prerequisite of any telephony service is the ability to deliver high-quality voice traffic. And it is fair to comment that this has been successfully established, tried and tested where many consumers benefit form this core service.
Network operators continually seek newer value-added services that will attract various consumers to their network, services and products. Operators offer data-centric services that build up on the already established core application; in its many guises we may have witnessed this evolvement as 2. To deliver effective data-centric services an increase in data throughput and a reliable medium needs to be provided.
GSM has established itself as a successful technology and has witnessed a series of extensions or upgrades. In the following sections we identify some of the extensions that are in operation today enabling faster data throughput for our demanding applications. These extensions Wide-area and Personal-area Communications 31 typically surround GSM, after all it is the most popular telecommunications technology in operation today.
Modifications to the GSM standard comprise a number of steps along the path to third generation and are typically characterized as 2. A user will make a call and the telephone network will direct or switch the call to the destination through a series of circuits whilst adopting an economical perspective.
In other words, it will make the least number of steps to get to its destination. Once a connection is established the circuits essentially create a dedicated pathway between source and destination. This pathway does not change nor can it be used by any other caller for the duration of the call.
GSM inherently offers data throughput of up to 9. This is achieved in the same way that voice traffic is digitized and then placed into a time slot; data is also allocated into time slots. HSCSD is capable of offering data speeds of up to approximately It achieves this throughput by taking advantage of the available time slots used within the TDMA scheme.
Instead of using one time slot, as it does for voice, it uses and reserves multiple time slots a maximum of four during a data-centric connection. Obviously, this will reduce the available number of slots for consumers making use of the voice service. With this scheme and the potential reduced capacity, operators charge the user for the duration and number of time slots occupied. With this introduction the general telecommunications community acknowledged that we had achieved one significant step in the evolutionary cellular generation scale.
Essentially, with GPRS we are at 2. CSD uses a series of circuits which remain unavailable during its use. A connectionless network allows users to enjoy a shared bandwidth in the same manner that the Internet does. Data packets are transmitted using time slots that are freely available, although in reality GPRS defines a set of classes, which mandate numerous transmission schemes. A particular class scheme will reserve upload and download time slots for low to high data transmission; each class would have varied throughput, but operators would charge accordingly for higher data rates.
Typically, users would experience a data rate of between GPRS was introduced with the primary objective to establish a much more efficient and cost effective solution for the user, in turn, enabling reliable data-centric applications. GPRS allows users to have an always-on presence, as operator charges only apply to data that is actually transmitted and received over the network. Essentially, this new modulation technique compresses and squeezes so much more into one time slot; remember we started with GSM merely offering us 9.
At the time of writing EDGE is very much prevalent in North America and in contrast, operators are contemplating skipping this mid-generation technology and heading straight towards third generation implementations in the majority of Europe. Ultimately, this infrastructure cannot endure changes to it on a regular basis; as a result we see architects modify or tweak the existing technology supported by the network. A deployment of established Wide-area and Personal-area Communications 33 base stations more about this later on a national scale would surely translate into an overwhelming unwillingness for operators to upgrade the associated hardware.
Naturally, making regular modifications incurs cost and would perhaps stagnate the advance of telecommunications. Some upgrades typically occur at a software level; for example, we can upgrade a piece of software on our notebook or cellular phone, so too can operators systematically upgrade their collection of stations with the ease of pushing a button.
Despite these innate reservations some modifications have to be made at the hardware level, primarily to accommodate the encoding and decoding of the 8PSK scheme. Cellular roaming With a good foundation upon which we can enjoy reliable voice and data services, we need to understand how collectively these technologies are brought together, after all we take these capabilities for granted and are able to use them no matter where we are in the world. We introduced in our earlier section the notion of base stations.
These units are distributed geographically and when we receive or make a call, the cellular terminal connects with its registered base station. The ability to roam from city to city is provided by a series of base stations that are strategically placed in proximity with each other. As the cellular user moves to the edge of coverage provided by one station viewed as a cell, see Figure 3. Network service providers will distribute base stations to create an optimum operating environment. Factors such as buildings, hills, mountains, valleys, the weather and so on, as well as potential interference that may be caused by the base stations themselves, are issues that are taken into consideration.
As a result, this technology enables cellular users to take their cell phone across several states and across the world allowing them to utilize the telephony service of a particular state or country; this is of course subject to the user having tri-band support within their cellular phone.
Third Generation 3G The rate at which new telecommunication standards are being developed is phenomenal. These areas may range from hundreds of meters to thousands of meters, depending upon the optimum operating environment. Remember, we can already rely on voice and, to an extent, data connectivity. Operators are always keen to create new scenarios where there is an increased and continued revenue stream.
The scope of these activities also extends to specifying new standards for third generation technology. This will ultimately benefit the operator, as there is a united driving force ensuring high-speed interoperable telecommunications standards. CDMA is a direct sequence DS technology utilizing a spread spectrum topology where multiple users occupy the radio channel and frequency concurrently we will discuss this in more detail later.
CDMA was initially developed by Qualcomm www. Wide-area and Personal-area Communications Table 3. This specification is pivotal in identifying key attributes of what characterizes third generation cellular technology. One glowing characteristic of the IMT specification is the attempt to bring together a cohesive cellular experience where world-wide cellular infrastructures interwork and interoperate. This translates into users being capable of utilizing one cellular phone and moving it from state to state and country to country with transparency and ease. In addition to providing cohesion, the IMT also defines the increasing need to deliver broader applications to include a range of multimedia services from a single cellular platform.
Numerous data rates are offered for a number of application contexts where a minimum of 2Mbps for cellular users, in a fixed location is offered, to lower data rates of Kbps and Kbps for mobile consumers, such as pedestrians and vehicle connectivity. The two methods offer complementary mechanisms each accommodating the various services that are available through UMTS. Instead, it uses all the available bandwidth for multiple users in the same channel, where codes are assigned to identify individual connections. Despite multiple users using the same channel no interference occurs between conversations.
It is the unique characteristics of the spread spectrum technique that makes this possible. In short, data is transmitted in its rawest form binary 1s and 0s and is spread over a channel in a pseudo-random pattern. Both the transmitter and receiver have agreed how to pseudo-randomly encode and decode the binary data. Similarly, with a number of potential callers engaged in a connection, a receiver will only listen to a particular conversation, that is, the conversation that has the right code. Wide-area and Personal-area Communications 37 The next generation of cellular applications Will we see the emergence of fourth generation 4G technology?
It is unclear at this stage what is meant by 4G; how it will be constituted and so on. Several companies believe that the technology will simply be an upgrade to 3G and others believe it will completely replace the existing infrastructure. The latter belief is somewhat difficult to understand, as so many companies have invested so much into delivering 3G technology. The proposed shift from 3G to 4G is beginning to take shape, albeit on a visionary basis only, as operators are in the process of deploying 3G cellular services. For example, within the United Kingdom several operators have only recently introduced 3G services for its consumer base.
Perhaps 4G will only exist as a concept, but its emergence as a full-bodied deployment, most certainly on a national basis, is still a long way off. Increasingly, with an eagerness to create better wireless applications, perhaps the emergence of 4G technology will itself exist as an amalgamation of wireless technologies, in turn, creating wireless convergence. Wireless Convergence Wireless convergence is a relatively new term which unites personal- and wide-area communications into a single solution and, indeed, it may describe itself as the new fourth generation.
It is the convergence of these technologies into a single product that provides a consumer with numerous methods of connectivity. We should also differentiate convergence and coexistence, as these describe two very different characteristics. In the early days of Bluetooth technology and the domination of Furthermore, many claims were made that other external factors, such as microwave ovens, would also affect the operation of these technologies. In short, coexistence refers to the operation of two technologies that use similar radio spectrums to deliver wireless applications; both Bluetooth and Currently, as we see the emergence of ZigBee also using the 2.
Nonetheless, we are assured that the Similarly, with the Specification of the Bluetooth System: Do consumers really need to know how it works? Many manufacturers are considering integrating many personal-area technologies into the cellular phone. We have already come to expect Infrared IrDA and Bluetooth as standard personal-area technologies, but some manufacturers are also considering integrating WiFi and in fact have already done so.
Some other applications may include Voice over Internet Protocol or VoIP — naturally, these two applications will require the presence of a hotspot as we illustrated in our anecdote within Chapter 2, Understanding the Wireless Audience. With the ability to utilize services and having the support of data connectivity across a cellular network, home and business users alike will be capable of connecting to a number of ISPs, in turn, allowing them to view web pages from the Internet or office Intranet. Similarly, users will also be able to send and receive emails.
This traditional method of connectivity is being largely replaced with the appearance of hotspots and, more recently, with the potential of Worldwide Interoperability for Microwave Access WiMAX , more about this later. It is predicted that with such an intense population of wireless hotspots, the need to utilize a dial-up connection will seem somewhat primitive. Perhaps manufacturers should focus on complementary technologies such as IrDA and Bluetooth. The former is a tried and trusted technology that enables users to synchronize and transfer files between a notebook and a phone.
Bluetooth is becoming more and more trusted and a reliable medium upon which consumers can achieve similar functionality. Indeed, users of Bluetooth-enabled cellular phones now come to expect headset operation as a standard feature.
CSD uses a series of circuits which remain unavailable during its use. In a group context, a Group Master Key GMK is generated again, in turn, generating additional keys to ultimately protect broadcast communication. But, the over complicated interwoven tapestry of a plot only reminds you of the eighth episode in series one where Carrie found her teenage love sweetheart, Ben in bed with her best friend Michael — someone save us please! When a cellular phone initiates a call, a frequency channel is reserved for the duration of that call; frequency modulation is then used to modulate voice data within the reserved frequency band. A fundamental prerequisite of any telephony service is the ability to deliver high-quality voice traffic.
However, Near Field Communications NFC is set to become a new technology that will add other complementary features to your phone. Primarily, Felica is a wireless smart card system that allows users to purchase shopping, cinema tickets and so on, using a cellular phone. When consumers reach the check-out point, payment can be made by passing the cellular phone across a wireless smart card reader; this notion is very similar to the e-wallet concept.
Wireless entry systems, such as e-logging provide users with the ability to enter buildings or to log on to a computer wirelessly. Again, the user would pass the cellular phone across the wireless reader. It is also envisaged that cellular phones will be used as a wireless entry system for your car and to start the engine. NFC has an operating range of 5cm 1. It uses magnetic induction to transmit data from one device to another and inherently provides secure and reliable transactions.
It mandates a peer-to-peer topology and is complementary to Bluetooth and WiFi. One such application in this particular context is to utilize NFC over Bluetooth and WiFi to enable hassle-free connectivity. With this particular application, users would no longer have to define parameters required to set-up a Bluetooth or a WiFi connection, as NFC would intelligently exchange the configuration parameters for you. Wireless convergence fulfils part of a wireless trend that ultimately provides a holistic range of applications that provide consumers with multiple choice options for connectivity, perpetuating the notion of mobility and freedom.
With an appropriate balance of consumer demand and wireless availability we can surely achieve a sense of reality in all our day-to-day expectations. Broadband wireless WiMAX is set to create an opportunity for permanent connectivity for users on the move or in the business and home. It essentially forms a hotspot that covers a radius of 10km 6 miles.
It forms part of a Metropolitan Area Network MAN that enables last mile connectivity for consumers by extending the fixed infrastructure over a short distance. More specifically, to deploy a cabled infrastructure for homes and offices can be an economical burden for telecommunication providers and WiMAX is perceived to deliver connectivity for a number of homes and businesses more cost effectively. It promises to deliver a shared bandwidth of up to 70Mbps over distances of 10km 6 miles ; we are assured that the bandwidth would be sufficient to meet the requirements of up to sixty businesses and a thousand homes.
With this level and potential range of connectivity we begin to blur the boundaries that exist for personal- and wide-area communications.