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From the Writers of Article1 and Article2 regarding Cellular Technology

Comes a Report Entitled



Rajkumar Periannan & Fadi Joseph Fahham


Introduction Cellular Systems Data Transmission over Existing Cellular Networks
Performance of the Digital Data Cellular Network A New Technology The Future..


When Marconi turned theory into practical reality in 1894, he had already seen the commercial possibility for a system of telegraphy, free from the limitations of wires. A century later, and the invention of the transistor has led to the ability for anyone to communicate while on the move.

Nowadays, it is a purely matter of convenience; receive and make calls at your leisure, any time and any place. The mobile phone has become a fashionable and everyday object.

In this "information age", most businessmen find it necessary to access data (such as files) while on the move. Rather than using a fixed terminal, which might not be available at the time, portable computers, directly connected to a cellular network, are more convenient especially for those who do a lot of travelling. These portable computers could be used to send and receive faxes, e-mails and other forms of data.


The main aim of this report is to examine the performance of the existing cellular networks to transmit data. First, the existing cellular network application of mobile telephones is discussed. This section gives an overview about the cellular network, a brief explanation on the events that occur when a call is made from or to a mobile telephone, and how cellular networks cope with frequency (or channel) allocation due to the increasing demand for mobile phones.

This is then followed by an explanation on how the cellular network could be used to transmit data. Two methods are introduced - Cellular Mobile Phone Service Network and the Digital Data Cellular network, with emphasis on the latter.
The limitations of the Digital Cellular network in transmitting data is considered and methods to minimise these are discussed. Finally, a new technology (CDMA) that does not use cellular networks has been briefly outlined


What is a Cellular Network

Elements of a Cellular Network

Operation of the Cellular Phone

Utilisation of the Spectrum in Cellular Networks


A cellular network[4] consists of mobile units linked via a radio network to an infrastructure of switching equipment interconnecting the different parts of the system and allowing access to the normal (fixed) Public Switched Telephone Network (PSTN).

To the mobile user, the main part of equipment is the handset and the radio unit; these could be separate units or an integral unit allowing portability. Additional units could be added to the basic unit - answering equipment, and data terminals.

A cellular radio telephone service differs from previous modes of mobile communications in a number of ways. One significant aspect is the improvement of the utilisation of the radio spectrum, made possible by the management techniques of the spectrum (e.g. frequency re-use) - discussed later.


In this section, the general system architecture of a cellular network are introduced:

  • Mobile Station (MS) : This is basically the mobile phone
  • Base Station (BS) : The covered area of a cellular network is divided into smaller areas called cells. Each cell has a base station which communicates simultaneously with all mobiles within the cell, and passes traffic to the Mobile Switching Centre. The base station is connected to the mobile phone via a radio interface.

  • Mobile Switching Centre (MSC) : This controls a number of cells (or cluster), arranges base stations and channels for the mobiles and handles connections.
  • National Carrier Exchange : This is the gateway to the national fixed public switched telephone network (PSTN). It handles connections on behalf of the national communication systems, and is usually integrated with the MSC.


When the mobile unit is active (i.e. when a mobile phone is switched on), it registers[5] with the appropriate BS , depending on its location, and its cell position is stored at the responsible MSC. When a call is set-up (when a user makes a call), the base station monitors the quality of the signal for the duration of the call, and reports that to the controlling MSC, which in turn makes decisions concerning the routing of the call.

When a cellular phone moves from one cell to the other, the BS will detect this from the signal power and inform the MSC of that. The MSC will then switch the control of the call to the BS of the new cell, where the phone is located. This is called handover . It normally takes up to 400ms, which is not noticeable for voice transmission.

A cellular phone user can only use his/her mobile within the covered area of the network. Roaming is the capacity of a cellular phone, registered on one system, to be able to enter and use other systems. Those other systems must be compatible to enable roaming (i.e. they must have the same type of networks). In Europe, the standard cellular network is called GSM (Global System for Mobile Communication). Incoming calls to GSM[8] users are routed to them, irrespective of where they are, as long as they are within Europe.


1.4.1 Frequency Re-use

In any radio network, the number of simultaneous calls that may occur is governed largely by the available frequency spectrum and the number of channels that can be supported by the available bandwidth.

In a conventional radio system (the previous modes of mobile communications) , groups (or areas) are allocated dedicated radio frequencies. In order to ensure that those channels are not affected by transmissions from other users operating at the same frequency, sufficient separation between the transmitters must be allowed for when allocating the frequencies.

In a cellular system,
frequency re-use[5] is achieved by assigning a subset of the total number of channels available to each base station, and controlling the power output of the transmitters. In this way, cellular networks increases capacity (number of channels available to users).
Adjacent cells are not allowed to operate at the same frequency since this causes interference between the cells.

From the above argument, it would seem that increasing the number of cells in the covered area (i.e. by decreasing the cell size) would increase the capacity. But by doing so, a number of difficulties arise:

  • Interference : decreasing the cell size, especially with a low repeat factor increases the problems of interference between cells which are using the same frequency.
  • Handovers: Decreasing the cell size increases the frequency of handovers, since a moving cellular phone would be changing cells more often. Since the MSC needs time to switch (for handovers), increasing the handovers will increase that time delay.

1.4.2 Microcellular Systems

It has been pointed out that decreasing the cell size increases capacity but causes other problems such as increased interference and time to handle handovers. However having an intelligent cell, which is able to monitor where exactly the mobile unit is and find a way to deliver confined power to that mobile unit, will increase channel capacity without causing these problems.
In a
microcellular system[1], each cell is divided into a number of microcells; each microcell (or zone) has a zone site and the cell itself has one base station. It is necessary to note that all the microcells, within a cell, use the same frequency used by that cell; that is no handovers occur between microcells.

Locating the mobile unit in a cell
An active mobile unit sends a signal to all zone sites, which in turn send a signal to the BS. A zone selector at the BS uses that signal to select a suitable zone to serve the mobile unit - choosing the zone with the strongest signal.

Base Station Signals
When a call is made to a cellular phone, the system already knows the cell location of that phone. The base station of that cell knows in which zone, within that cell, the cellular phone is located. Therefore when it receives the signal, the base station transmits it to the suitable zone site. The zone site receives the cellular signal from the base station and transmits that signal to the mobile phone after amplification. By confining the power transmitted to the mobile phone, co-channel interference is reduced between the zones and the capacity of system is increased.

The benefits of Microcellular systems

  • Interference reduced (compared to decreasing the cell size)
  • Handovers reduced (also compared to decreasing the cell size) since the microcells within the cell operate at the same frequency; no handover occurs when the mobile unit moves between the microcells
  • Size of the zone apparatus. The zone site equipment are small, so the can be mounted on the side of a building of on poles.
  • Increased system capacity. The microcell is an intelligent cell. The new microcell knows where to locate the mobile unit in a particular zone of the cell and deliver the power to that zone. Since the signal power is reduced, the microcells can be closer and therefore increase capacity

However, in microcellular system, the transmitted power to a mobile phone within a microcell has to be precise; too much power results in interference between microcells, while too little power and the signal might not reach the mobile phone.
This is a drawback of microcellular systems, since a change in the surrounding (a new building, say, within a microcell) will require a change of the transmission power.

1.4.3 Multiple Access Systems

In digital cellular networks,
Multiple access systems[6] are used to allow simultaneous users to share the same channel within a cell. The common methods are time division multiple access (TDMA) and frequency division multiple access (FDMA).

In TDMA, the bandwidth allocated for the channel is divided into time slots - the number of slots depends on the system. Each user is then allocated a slot, and hence multiple users share the same frequency but at different times.
In FDMA, the channel is divided into frequency bands, and each user is allocated a frequency band.


CMPS for Data Transmission

Digital Data Cellular Network for Data Transmission

The cellular network described in section 1 is a form of Cellular Mobile Phone Service (CMPS) network meant especially for mobile phone services. Therefore we have so far considered voice transmission on the cellular network. Now transmission that allows transactions such as sending an e-mail to a remote user or a portable computer talking to a central database is considered. This form of transaction requires data transmission and can be done using the existing cellular networks. Now, a discussion of data transmission on existing cellular networks is presented.

Here, two ways in which the cellular network can be used for data transmission are explained. They are
  • Using the existing CMPS with no architectural modification. CMPS is a circuit-switched network which means once a connection has been made between two telephones, this connection would be dedicated to these telephones for the whole conversation.
  • Using a Digital Data Cellular Network.
    This network unlike the CMPS would use packet switched technology and requires slight architectural modification to the CMPS. A conceptual model of the Digital Data Cellular Network is used to explain this method of data transmission.
More emphasis will be given on the second method, since it is more suitable than the first for data transmission (
explained later).


The cellular network architecture used in this method remains the same as the architecture in section 1. There would be protocol changes required but this will not be discussed as it does not help in the explanation below.

In this section, handover and the solution to overcome this problem is discussed as handover is a major problem in transmitting data. This is due to the lack of redundancy in data (unlike speech) which does not allow a section of missing data to be reconstructed using data before and afterwards.

Before going any further certain terms used in this section are explained.

A data terminal in this context is typically a portable computer such as a laptop without its own antenna. This data terminal is connected to a Mobile Station in order to gain access to the CMPS network. Recall, the MS could refer to the mobile phone (introduced in section 1). However, take note that MS is any device that has an antenna that receives and transmits signals.

The Base Station Controller (BSC) and the Base Station Transmitter (BST) are the components within the BS.

2.1.1 Coping with Handover

When the vehicle containing the MS and the data terminal moves from one cell to another, handover occurs. When handover occurs the channel the MS was using before can no longer be used. Since the CMPS network uses circuit-switch technology, a new channel needs to be allocated in order to make the link continuously available. This new channel would be allocated by the BS in the new cell. The whole handover event takes 400ms and results in a line break during this time.
In order to prevent data loss during this time buffering is provided.

2.1.2 Buffering

Once handover occurs, the MS and the BS stops transmitting data. However, both of them will still be receiving data from the data terminal and the PSTN network respectively. Therefore the buffer needs to be implemented in two places. One between the data terminal and the MS for upward transmission (transmission from MS to BS) and the other between the BSC and the BTC for downward transmission (opposite to upward).

The diagram below illustrates these queues.

Mathematical analysis[2] on these queues have proven that they reduce the handover problem significantly.
However, this network is still not as suitable as the network described below.


As explained before, CMPS is a network which uses circuit-switched technology that allocates dedicated line between two users. In order to establish this line, a call setup procedure has to be followed.

For data transmission, the call setup procedure introduces long delays which become unacceptable especially when the data traffic comes in largely spaced bursts of data blocks.
Therefore in order to transmit data, a packet switched network is needed and Digital Data Cellular Network is a network of this form. Here, the MS would transmit and receive data packets only when asked by the base station (more detail in section 2.2.2). Therefore there is no permanent connection between the MS and the BS. Only a virtual connection exists between them.
So no call setup is needed for the MS to send and receive data from the BS.

In order to illustrate data transmission in this form of cellular networks, a conceptual Digital Data Cellular network model created by Dr.Sergio Coury in his thesis entitled Quantitative Models for the Design of Cellular Networks is used. This conceptual model would be refereed to as MCN and it is flexible enough to be adapted to any other Digital Data Cellular Network that transmits data.

As this model is already known to be better in transmitting data than the CMPS, this model would be discussed in detail. The performance of the cellular network in transmitting data would be based on this cellular network model. But before the performance issue is considered, three important aspects of this network is explained in order to give sufficient background on how this network works. These three important aspects are :

  • Modification to the cellular network architecture described in section 1 to form the MCN architecture
  • Protocols used in MCN
  • Buffer Administration techniques used in MCN
Note that although these topics are about the MCN network, they are applicable to any other Digital Data Cellular Network with slight variations.

2.2.1 Architecture Modifications

The MSC is now replaced by a packet switch exchange since packet switch technology is used. The diagram below shows the overall architecture of this network.

An example of a digital cellular network that is opened for public service is Paknet, a joint venture company between Racal Telecom and Mercury Communications.
Other than the change illustrated above, everything else about the architecture remains the same with that of CMPS. There is still a central computer accessible by all the base stations which continuously monitors the location of the MSs. Even now when an MS moves to another cell, handover occurs and control is handed to another BS.
The cell operation and spectrum utilisation methods remain the same as the architecture described in section 1.

2.2.2 Medium Access Protocols

Protocols define a set of steps which allows meaningful conversation to take place. In cellular networks, a set of protocols, which describes the data that is to be transmitted and to be expected by both mobile station and base station, is defined . This allows these components within the cellular network to know what and when to listen, transmit and receive the relevant data. This data could be either control information or the information itself.

2.2.3 The Protocol

The protocol described here is a combination of TDMA and Polling. The right to access each channel is controlled by the BS. In the channels, data packets are transmitted at discrete time intervals known as time slots.

There are three kinds of channels. They are control, uplink data transfer and downlink data transfer channels.

The uplink data transfer channel is used to transmit packets from the MS to the BS while the downlink data transfer channel is used to transmit packets in the opposite direction.

The control channel transmits system packets from the BS to all the MSs in the cell. The most important contents of these packets are the Header and the Data Assignment Table (DAT). The Header contains information regarding number of channels available and its corresponding frequency. Meanwhile, the DAT acts to inform which MSs are allowed to transmit and receive packets in the next time slot.

In the next time slot, the MS informed to transmit uses the appropriate upward data transfer channel to transmit packets if it has message, otherwise a null reply is sent. This shows that the BS is effectively polling the MSs to transmit packets in the upward channel.
The MS informed to receive tunes to the selected downward transfer channel and receive the packets.

2.2.4 Buffer Administration Technique

The MS and the BS receive and transmit data packets. If the MS has only one receiver, it can only tune into one channel at a time and receive a single packet from this channel time slot. So, the packets that arrive at the base station from the packet switch exchange, meant for several MSs, have to be queued and forwarded one at a time to the appropriate transmitting channel (channel which the MS is waiting to receive the packets from). Transmitting more than a single packet to a mobile station would result in packet overlap and thus packet loss.

Buffer administration Techniques describes how the arriving packets are queued and selected to be transmitted from the BS to the appropriate MS.

There are three Buffer Administration Techniques :-

  1. Cyclic Polling
  2. Channel Splitting
  3. Reservation Cyclic Polling

In this technique there is an arbitrary number of queues of fixed capacity. Each MS has its own queue that is not shared with other MSs. There are several number of transmitters. This system would consist of a single server (channel controller) which would repeat the following steps :-

  1. Check the queue for any packet.
    1. If there are, then send the packet to a free transmitter
    2. If there are no packets, then move to the next queue
repeat step (I) until
  1. all the queues have been visited
  2. there are no free transmitters.

And then point to the next queue to be visited in the next discrete time slot.

The diagram below illustrates this technique Channel Split Technique

This is the same as the Cyclic Polling Technique but it has several channel controllers which operate in parallel. Each channel controller is dedicated to a group which consists of several queues. Each group of queues also has its own dedicated transmitter. Packets queued in a group can only be transmitted using this group's transmitter.

The diagram below illustrates this graphically.

The steps performed by the channel controller still remains the same as cyclic polling but now it only visits the queues in its group. Reservation Technique

In this technique, similar to the Channel Split Technique, the transmitters are dedicated to groups. But now, in each group there is only a single queue. The incoming stream of packets which would have been put into different queues within a group in the Channel Splitting Technique would be put into this single queue. Therefore the queue capacity in this technique is normally multiples of the queue capacity in both Channel and Cyclic Polling Techniques.

The diagram below illustrates this technique


The Digital Data Cellular Network has many limitations which affects its performance in transmitting data. These includes congestion at the base station, fading, breaks during handovers and co-channel interference. More emphasis is placed on the congestion limitation as it depends on the design of the cellular system. On the other hand the other limitations, such as fading and co-channel interference depend mostly on the nature of the radio signal.

2.3.1 Congestion

Congestion is said to occur at a BS when it does not have enough space in its queues to put the new arriving packets. These new packets would then be lost. Congestion leads to the packets already in the queue to wait the longest time before being transmitted.
So, congestion introduces unacceptable packet delay

This congestion problem cannot be completely avoided but it can be minimised by

  1. choosing the correct buffer administration technique. This reduces congestion at the BS transmit buffer.
  2. Increasing the number of channels per cell. Doing this reduces congestion at both the receive and transmit buffer of the BS.
  3. reducing the rate at which BS informs MS to transmit data. This reduces congestion at the BS receive buffer Choosing the Best Buffer Administration Technique

The best technique should be able to support a large rate of packet arrival without any queue overflow. It should also cause minimal congestion when both large and moderate amount of packets arrive (high and moderate incoming traffic ). Therefore in order to identify the best technique, the different techniques discussed are compared with respect to the
  1. maximum arrival rate it supports
  2. its performance at moderate and high incoming traffic levels
This is followed by a discussion on methods that could be used to improve these buffer administration techniques in order to get better performance. (For the purpose of comparison, both Channel Splitting and Cyclic Polling Techniques are assumed to have the same queue capacity).

(a) Maximum Rate of Packet Arrival Supported

The maximum packet arrival rate supported is the maximum rate at which the packets can arrive without any increase in the number of packets stored in the transmit multi-level queue.
This occurs when the base station is operating at a steady state where the average number of arrivals in the system is less than the maximum number of departures during a time slot.

When the base station stops operating in the steady state, the amount of free queue space decreases and would eventually lead to queue overflow. This leads to congestion.

mathematical analysis[3] of the system can show that the cyclic polling technique supports the highest arrival rate while still maintaining steady state operation of the BS. Both the Channel Split and the Reservation Techniques support the same rate of packet arrival for steady state operation.


When the packet arrival rate is unequal in each queue (which is normally the case) , in both the Reservation and Channel Splitting Techniques, the transmitters allocated to the queues with lower arrival rate will be inefficiently used.
Meanwhile, the Cyclic Polling Technique would use all its transmitters efficiently since any one of these transmitters can be used to transmit the packets.

(b) Incoming Traffic Level Supported

The BS is said to support an incoming traffic level when it can operate without any queue overflow and the packets queued has acceptable mean waiting time in the queue.
The incoming traffic level considered here can be divided into moderate and high levels.
Mathematical analysis[3] shows that the results obtained for both moderate and high incoming traffic levels are the same.

The Reservation Technique gives the best support for both traffic levels without any possibility of queue overflow. The Cyclic Polling Technique gives the second best support followed by the Channel Splitting Technique.


Since the queue capacity in the Reservation Technique is the largest, it can accommodate larger number of packets at both incoming traffic levels. Since both Cyclic Polling and Channel Splitting Techniques have the same queue size, the inefficient use of the transmitters in the Channel Splitting Technique causes the Cyclic Polling Technique to have a better ability to prevent queue overflow.

However, the reservation channel causes the highest mean waiting time of the packets in the queue. The Cyclic Polling Technique gives the lowest mean waiting time followed by the Channel Splitting Technique.


The queues in the Reservation Technique which has a higher capacity than the rest causes more packets to be queued. So, any packet in the queue has to wait longer before getting transmitted. In the Cyclic Polling Technique, the packets have lower mean waiting time than the Channel Split Technique as it uses the transmitters more efficiently.

Final point on buffer administration techniques

  1. The Cyclic Polling Technique supports the highest maximum rate of packet arrival without any possibility of congestion.
  2. The Reservation Technique gives support to the highest number of arriving packets without any possibility of congestion at the expense of an increased packet delay.

Here, we can only conclude that there is no single technique that could be regarded as the best. The best technique to minimise congestion depends on the situation. Recall, there are two situations here; the incoming traffic level and the rate at which packets arrive. The cost factor has not been considered here. This could significantly affect the choice of the best technique as well. At the end of the day, it is up to the designer to weigh out what is of importance and what situations are more likely to happen to choose a suitable technique. Improvement on the Buffer Administration Techniques to Reduce Congestion

In the techniques described above both the queue size and the number of transmitter channel allocated does not change. These are two main points that are improved upon below.

i. Dynamic changes in the queue size

The queue size is changed depending on the rate of packet arrival to the queue. In all three, techniques this would lead to reduction in queue overflow. The queue with a higher rate or number of packet arrival should be allocated a larger queue space. This could be obtained from the queues with lower rate or number of packet arrival respectively.

In order to do this extra intelligence to monitor the rates and number of packet arrival to all the queues is needed. The system should then be able to predict future arrivals based on the previous data obtained. This system should also be able to determine the optimal queue size needed as increasing the size too much would lead to an increase in the mean waiting time of packets.

ii. Dynamic Channel Assignment

One of the main reasons packet overflow occurs in both Reservation and Channel Splitting Techniques is because of the limited number of transmitter channels available in each group.
So an improvement would be to add intelligence that allocates channels to groups that has higher rate or number of packet arrival. Again the same intelligence, as discussed above, is needed.

Disadvantage of the Improvement Methods Suggested

Both dynamic channel and queue size assignment requires extra processing power. This could prove to be very costly to implement.

But on the other hand if these methods give an improvement that is more than proportionate to the cost increase, it would be prudent to implement a queuing system with these improved techniques. Rate At Which BS Polls MS

The BS controls the rate at which a MS transmits data since the MS transmits data only if it had been polled to do so in the previous time slot (refer section 2.2.2). If the rate is too high the receive buffer for this MS in the BS would be congested.


Reduce the rate at which the BS polls the MS to transmit packets in the upward data transfer channel. Care must be taken not to reduce the polling rate too much as this can cause the transmit buffer in the MS to suffer queue overflow. Number of Channels Per Cell

When the number of channels per cell is small (less transmitting channels) base station congestion is very likely to occur. Increasing the number of channels to solve this problem could be a problem since :-
the bandwidth allocated for uplink and downlink transmission is fixed. Therefore increasing the channel number per cell would cause the channel frequencies used in a cell to be re-used in a closer cell. This increases co-channel interference.


Use a microcellular network since it can increase the number of channels per cell without an increase in co-channel interference (see section 1.4.2).

2.3.2 Fading

This is the reduction of signal power. Fading is caused by many factors - the most important ones being multipath and shielding.

Multipath fading is caused by the transmission of the signal along different paths and resulting in simultaneous reception. Depending of the amplitudes and phase of the signal, the result of this could be that the signals cancel each other completely or significant attenuation in the resultant signal.

Shielding is the absence of field strength. Most common causes are tunnels, hills and inside certain buildings.


The receiver at the BS should have an Equaliser[7] circuit to compensate for fading. Equaliser finds how a known transmitted signal(transmitted with the desired signal)was modified by multipath fading and shielding. Using this information, an inverse filter is constructed and the desired signal is extracted.

2.3.3 Co-Channel Interference

Co-channels are the same channels (or frequencies) that are used by different cells. To avoid this kind of interference, it is necessary to separate the co-channels by as great distance as possible. But, by doing so, channel capacity will be compromised.

Here, microcells could be used to decrease co-channel interference for a particular capacity wanted. Alternatively, the Equaliser can also be used to minimise the effect of co-channel interference on the desired signal.

2.3.4 Handovers

Handover does not pose serious problems in Digital Data Cellular Networks.

In circuit-switch networks, handover is a major problem , because the radio link between the MS and the BS which is continuously available is lost. During the time in which the link is lost, both the MS and the BS could be transmitting data which will be lost unless effective buffering is provided (see section 2.2).
In Digital Data Cellular Network considered, there is no continuous link between the MS and the BS. Packets are transmitted and received by the MS only after the BS informs it to do so. So, the link between the MS and the BS only lasts for one time slot (time in which a packet can be transmitted and received). Therefore, handover can only cause, if any, a few packet loss and does not pose a serious problem.


Due to the rapid growth in the cellular communication industry, there is an increased need for greater system capacity. Code division multiple access (or CDMA[9]) is the new technology, and it does not need a cellular structure.

CDMA is a 'spread spectrum' technology; it spreads the information contained in a particular signal over the entire bandwidth allocated for the mobile communication. With CDMA, unique digital codes, rather than radio frequencies or channels, are used to differentiate the different signals. These codes are shared by both the transmitter and receiver; and hence the receiver (the mobile phone) receives all the signals but can only recognise the one with the same codes.

CDMA has many advantages over the existing cellular systems

  • Increases capacity and improves quality of the signal.
  • Simplified system planning through the use of the same frequency all over the covered area.
  • Enhanced privacy
However, CDMA can only be used for digital transmission, unlike the cellular system. This makes the move towards CDMA in some countries, which do not use the digital system, a distant future.


Currently, there are different standards of cellular systems in different parts of the world; the major ones are the GSM in Europe, and the PCS in North America. Roaming is not possible between these two systems. The next step would be to have duel-mode phones which could operate in the two different systems at the touch of a button. Having one global cellular communication system is ideal, but will take a while, since it will require altering one system's hardward (which costs a lot of money!)

Since we are in the "information age" and due to the rapid growth of the cellular system, one could predict that in the very near future, everyone will have a portable communication terminal, which is small in size, fast in accessing the internet and transmit/receive data, cheaper, and could virtually be used from anywhere in the system.

Finally, celluar networks will soon be replaced by the spread specturm technology; this move has already began in some parts of the world and the rest will sure to follow.



BS Base Station
CDMA Code Division Multiple Access
CMPS Cellular Mobile Phone Services
FDMA Frequency Division Multiple Access
MS Mobile Station
MSC Mobile Switching Centre
PSTN Public Switched Telephone Network
TDMA Time Division Multiple Access


1. Title: Mobile Cellular Telecommunications - Analog and Digital Systems
Author(s): Lee W.C.Y.
Source: 2nd Edition, McGraw-Hill, Inc.
Chapter 16, pg 563. Gives a very good explanation of microcells(intelligent cell).
    Usefulness: @ @ @ @ Readability: @ @ @ @
2. Title: Performance Analysis of Cellular Mobile Communication Systems for Data Transmission
Author(s): Wang C.
Source: IEEE Transactions on Vehicular Technology, Vol. 44, NO.1, 1995
A detailed analysis of the performance in queuing data in the CD/MD/1/N queue during handover
    Usefulness: @ @ @ @ Readability: @ @
3. Title: Quantitative Models For the Design of Cellular Networks
Author(s): Coury S.
Source: 1993 PHd thesis.
Covers most of the conceptual Digital Data Cellular Network(MCN) introduced in great detail.
    Usefulness: @ @ @ @ Readability: @ @ @
4. Title: Cellular Communications for Data Transmission
Author(s): Flack M., Gronow M.
Source: NCC Blackwell Limited.
Chapter 1 and 2. Gives a very good overview about cellular networks.
    Usefulness: @ @ @ @ Readability: @ @ @
5. Title: Existing Cellular Network Technology - Mobile Phones
Author(s): Periannan R.
Source: <>
This site explains the architecture of Cellular Mobile Phone Services(CMPS) network in more detail. It also introduces the frequency re-use concept.
    Usefuleness: @ @ @ Readability: @ @ @ @
6. Title: Mobile Phones in the UK and Multiple Access Systems
Author(s): Fahham F.J.
Source: <>
This site explains the architecture of Cellular Mobile Phone Services(CMPS) network in more detail. It also introduces the frequency re-use concept.
    Usefuleness: @ @ @ Readability: @ @ @ @
7. Title: Overview of the Global System for Mobile Communications
Author(s): Scourias J.
Source: <>
This site explains how the equaliser functions in more detail.
    Usefuleness: @ @ @ Readability: @ @ @
8. Title: Overview of the Global System for Mobile Communications
Author(s): Scourias J.
Source: <>
This site explains how roaming in GSM works in detail.
    Usefuleness: @ @ Readability: @ @ @
9. Title: CDMA - Principles of Spread Spectrum Communication
Author(s): Viterbi A.J.
Source: Addison-Wesley Wireless Communication Series.
Chapter 1 and 2. A detailed explanation about CDMA.
    Usefulness: @ @ Readability: @ @