The idea of letting vehicles communicate with each other has given rise to a vast number of novel applications that provide value added services to travellers, such as information, advertisements, and entertainment, to make their journeys convenient and enjoyable. However, these applications may require more throughput than conventional safety applications. Cognitive Radio (CR) technology has been considered as a potential solution to satisfy the throughput demands of Vehicular Ad Hoc Networks (VANETs). Infotainment applications may be offered on Television White Spaces (TVWS) employing CRs. Nevertheless, a proper mechanism is required to discover services offered on TVWS, and also to establish and maintain connections between a provider and a user of application services. This necessitates a communication channel common to all the nodes in a vehicular network to exchange signalling information. Nonetheless, our simulations indicate severe packet losses when a single channel is used for this purpose. In this paper, we present a service management framework that employs multiple channels in the Dedicated Short Range Communications (DSRC) spectrum in accordance with the IEEE Wireless Access in Vehicular Environments (WAVE) standard while continuously evaluating channel congestion. We implement our algorithm on the well-known discreet event simulator OMNeT++. The results show a significant improvement up to 91% in the packet reception using the developed multi-channel framework.

In radiometric fingerprinting, a transmitter is identified from its unique electromagnetic emission. A unique radiometric fingerprint can be used to establish the identity of a specific wireless device in order to prevent masquerading/impersonation attacks. Recent research in radiometric fingerprinting have introduced promising new features and techniques to demonstrate its feasibility for security and privacy applications in wireless devices. However less attention is given to the robustness of radiometric fingerprint against impersonation attacks. In our previous work, we have evaluated the impersonation attack on radiometric fingerprinting using low-cost transceivers. In our previous work, the impersonator was unaware of its own transceiver impairments, which leads to lower success rate. In this research work we are considering a sophisticated impersonator aware of its transceiver response and producing an impairment free legitimate radio signal of the target device. Our analysis shows that successful impersonation is largely dependent on the quality of the legitimate receiver.

Traditionally, enhancing the safety of commuters and relieving traffic congestion have been the primary objectives of Vehicular Ad hoc Networks (VANETs). Recently, much progress has been made in the field of vehicular communication, enabling futuristic applications that might make journeys more enjoyable to passengers, such as exchanging multimedia among passengers in nearby vehicles. However, these applications may require more throughput than conventional safety applications. Cognitive Radio (CR) technology is a potential solution to satisfy the throughput demands of VANETs. Typically, in communication networks as large as vehicular networks simulation is the preferred approach to performance evaluation of new protocol concepts. Although, simulation frameworks for VANETs are openly available, simulators capable of assessing end-to-end real-life applications of CR enabled VANETs are never made available to the research community. In this paper, we present a simulation framework for CR-VANETs called SimuCRV, based on the well-known discrete event simulator OMNeT++. The framework extends the vehicular network simulation framework called Veins and facilitates advertising of cognitive radio based services according to the IEEE Wireless Access in Vehicular Environments (WAVE) standard. We demonstrate the effectiveness of our framework through a simulation scenario where we compare the throughput of a road side unit (RSU) having a single transceiver with a dual radio based RSU that distributes its application data on a CR channel.

This paper quantifies the effects of sharing spectrum between two cellular network operators and its impact on the number of base stations required to meet capacity targets. In particular, it shows the effects of traffic profiles with asymmetric loads on the spectrum sharing dividends. The traffic profiles presented use actual time-of-day data from two different cellular operators using two shared 1800 MHz LTE sites, one urban and one rural. The data is used to illustrate that if the two operators shared spectrum across the operators' networks a spectrum sharing gain of 25% would result. This means that 25% fewer base stations would be required to meet the forecasted capacity load at the cell edge. The analysis is useful to both cellular operators and to spectrum regulators. To operators, this paper presents methods and examples using measured data to calculate the benefits of sharing spectrum. To regulators, this paper offers data to show that sharing licensed spectrum between operators can reduce the total number of cell sites that are required to meet forecasted increases in capacity demand.

This paper presents an adaptive multiuser transceiver scheme for DS-CDMA systems in which pilot symbols are added to users’ data to estimate complex channel fading coefficients. The performance of receiver antenna diversity with maximal ratio combining (MRC) technique is analyzed for imperfect channel estimation in flat fading environments. The complex fading coefficients are estimated using least mean square (LMS) algorithm and these coefficients are utilized by the maximal ratio combiner for generating the decision variable. Probability of error in closed form is derived. Further, the effect of pilot signal power on bit error rate (BER) and BER performance of multiplexed pilot and data signal transmission scenario are investigated. We have compared the performance of added and multiplexed pilot-data systems and concluded the advantages of both systems. The proposed CDMA technique uses the chaotic sequence as spreading sequence. Assuming proper synchronization, the computer simulation results demonstrate the better bit error rate performance in the presence of channel estimator in the chaotic based CDMA system and the receiver antenna diversity technique further improves the performance of the proposed system. Also, no channel estimator is required if there is no phase distortion to the transmitted signal.

This paper presents the antijamming performance of adaptive multiuser DS-CDMA system using maximal ratio combining technique in slow switching pulse noise jammer. Complex flat fading channel coefficients are assumed to be unknown at the receiver. Pilot symbols are used to estimate the fading coefficients using least mean square (LMS) algorithm, and effect of imperfect channel estimation on bit error rate (BER) is studied. Under the perfect synchronization conditions, probability of error in closed form is derived.

This paper presents a comparative analysis of eigenvector-based signal detection algorithms and a new eigenvector-based modulation classifier for multiple antenna cognitive radio applications. The signal detection algorithms considered in this work are: Feature Template Matching (FTM), Multiple Feature Matching (MFM) and Principal Components (PC)-based detection. A software-defined radio (SDR) platform is used to experimentally evaluate the detection performance of these algorithms. It is observed that MFM, which uses four signal features extracted across space, time and phase dimensions, provides the best performance among the considered algorithms. This paper also presents a new idea on the use of eigenvectors for signal classification in multiple antenna systems. Using computer simulations, it is shown that eigenvectors corresponding to different modulation schemes allow for reliable signal identification even at very low SNR values (on the order of -20 dB), therefore they can be used effectively for signal classification in cognitive radio applications.

Driven by a combination of flat lining revenues and an explosive growth in the mobile data traffic and hence the need for network resources, mobile operators consider infrastructure-and spectrum sharing as a means to reduce operational costs. We develop and apply an assessment approach to quantify the benefits associated with spectrum sharing in an infrastructure-shared environment, and estimate the evolution of the derived ‘spectrum sharing dividend’ as traffic loads, radio access technologies, spectrum availability and performance targets change over time. The obtained insights can assist operators and regulators in their assessment of the merit of spectrum sharing. Analysis shows that operators with loads that peak at different times continue to benefit significantly by sharing spectrum, despite the diminishing ‘trunking gains’ of spectrum sharing as individual operator loads and capacities increase over time.

Recently, radio‐frequency (RF) fingerprinting has been proposed for mitigating primary user emulation (PUE) attacks in cognitive radio networks (CRNs). The widespread practical implementation of cognitive radio (CR) is likely to utilise software‐defined radios with a low‐end (i.e. low‐cost) receiver built with inexpensive analogue components. This study experimentally analyses the feasibility of RF fingerprinting for mitigating PUE attacks using low‐end software‐defined CRs. Seven universal software radio peripherals are used as low‐end CR receivers and their resulting performance is analysed for ad hoc and infrastructure CRN scenarios. The performance analysis is performed for the largest known data set of its kind, which consists of 490 000 measurements from seven identical transmitters across eight receivers. It is found that impairments in the front‐end of a low‐end receiver affects the accuracy of transmitter classification and this accuracy varies across receivers. The results suggest that RF fingerprinting can be effectively used for mitigating PUE attacks in an ad hoc CRN at high receiver signal‐to‐noise ratio whereas RF fingerprinting is not a practical solution for mitigating PUE attacks in an infrastructure CRN.

Radio Frequency (RF) fingerprinting is a technique, where a transmitter is identified from its electromagnetic emission. Most existing RF fingerprinting techniques have been evaluated with high-end receivers and promising classification results have been reported in the literature. However, the realization of RF fingerprinting in todays low-end (i.e. low cost) portable devices requires the validation of the existing RF fingerprinting techniques with low-end receivers. This contribution analyzes the performance of RF fingerprinting for low-end receivers. Experiments are performed for three transmitters and signals are captured with one high-end receiver and three low-end receivers using Universal Software Radio Peripheral (USRP). It is found that the classification accuracy of RF fingerprinting varies for different low-end receivers. Results show that low-end receivers provide good classification results at high receiver SNR but high receiver SNR is rare in a typical wireless communication environment. Whereas high-end receiver performs well even at low SNR.

In the recent past considerable research has been performed on blind signal detection techniques that exploit the covariance matrix of the signals received at a cognitive radio (CR). These techniques overcome the noise uncertainty problem of the energy detection (ED) method and can even perform better than ED for correlated signals. Contrary to the previous work where the main evaluation technique has been theoretical analysis and simulations, in this paper we use Software defined radios (SDRs) with correlated signal reception capability to evaluate the sensing performance of the existing covariance based detection (CBD) techniques. The existing techniques considered in this work are; Covariance absolute value (CAV), Maximum-minimum eigenvalue (MME), Energy with minimum eigenvalue (EME) and Maximum eigenvalue detection (MED). Most importantly this paper presents a novel technique for blind signal detection that uses Principal Component (PC) Analysis. The PC based signal detection algorithm and the CBD algorithms are tested in a real scenario with SDRs and their sensing performance is compared. The PC algorithm outperforms the MED and EME algorithms under all conditions and it performs better than the MME and CAV algorithms under certain conditions.

The operation of unlicensed devices (UDs) on underutilized licensed frequency bands can significantly enhance spectrum utilization. The FCC regulations on UD operation on vacant TV channels focus on controlling the interference to the primary system, which is a critical operational requirement for UDs. Personal/portable UDs are allowed adjacent channel operation inside the TV service contour. However, the FCC analysis of this operation is based on interference effects of a single UD, while the accumulative interference from multiple UDs is not considered. In this paper we extend the FCC analysis and develop a realistic model for interference from multiple UDs operating in Wireless Local Area Network (WLAN) clusters. We develop analytical expressions for the probability of outage of a primary user (PU) interfered by single and multiple clusters. The effect of channel variability due to shadowing is included. Results present the increase in PU outage probability with increased PU-TV station distance. For a single cluster operating in close vicinity of a PU, we analyse the effects of UD transmit power control and radiation pattern on PU performance.

Cognitive radios (CRs) improve spectral efficiency by transmitting unlicensed signals over licensed frequency bands. A key requirement for CRs is to limit the interference to the licensed system. However, the variability in the radio channel caused by fading and shadowing makes this task more difficult. In this paper the performance of the licensed system has been analysed by calculating the probability of outage of the licensed receiver (LR). A Poisson field of CRs is considered such that the CRs are distributed uniformly around the LR. A circular exclusion zone of radius R has been defined with the LR at the center so that CRs are permitted to transmit only if they are outside this zone. For the first time, expressions for outage probabilities have been developed for different values of R, taking into account the variability in the radio channel. Rayleigh, lognormal and Suzuki channels have been analysed. The effects of channel characteristics on the outage probability have been investigated. Results show the extent to which increasing R improves the performance of the licensed system significantly.

Using indoor propagation measurements, the combined effect of received signal strength (RSS) and traffic type (i.e., voice and video) on the performance of a typical WLAN is investigated. In the investigation, both ad hoc and infrastructure network scenarios are used. Measurement results obtained show that RSS has a significant effect on the playback delays of voice and video traffic, especially under higher bit rates. In addition, we study the relationship between wireless channel state and the user-perceived quality of audio and video streaming applications. Finally, we evaluate (by simulation) the number of simultaneous voice and video clients that an IEEE 802.1 lg AP can support. Results show that the performance of a typical IEEE 802.1 lg AP significantly deteriorates for N > 15 clients. Our findings show the practicality of deploying indoor WLANs for multimedia applications.

Cooperative diversity can be applied to energy-constrained wireless sensor networks to significantly reduce node energy consumption. However, cooperation partners must be carefully selected and coordinated to practically exploit this energy saving potential. In this paper we investigate partner choice for energy efficient cooperation in a wireless sensor network. We formulate novel and computationally efficient partner choice heuristics for sensor nodes based on either global or local knowledge of average path loss values in the network. We present extensive simulation results of cooperation in a wireless sensor network to show that the proposed heuristics achieve near-optimally energy efficient partner selection. Our results also demonstrate that large network-wide energy savings are achieved as a result of cooperative communication. Therefore, our simple partner choice heuristics form the basis of an effective distributed cooperation protocol for improving the energy efficiency of a wireless sensor network. Very importantly from the point of view of practical implementation, we show that our partner choice heuristic based on local information is the most effective cooperation strategy for resource-constrained wireless sensor networks, as it yields superior energy conservation results while enabling fully distributed and scalable cooperation.

Energy efficient communication is a key requirement of energy-constrained wireless sensor networks. Cooperative diversity can be applied to wireless sensor networks to significantly reduce node energy consumption. However, judicious selection and coordination of cooperation partners is essential to exploiting this energy saving potential of cooperation. In this paper we investigate optimal partner choice and power allocation for energy efficient cooperation in wireless sensor networks. Our insights lead us to formulate power allocation and partner choice heuristics which form a simple and practical cooperation strategy for energy-constrained wireless sensor networks, allowing nodes to autonomously make near-optimal cooperation decisions. We show that the power allocation optimisation problem is non-linear, necessitating the use of a search to find the optimum solution. We present the resulting cooperative energy savings in terms of network geometry for a range of potential partner locations. Our results reveal that the partner-destination and the source-partner channels have roughly equal influence over cooperation decisions for optimal energy efficiency. We use this observation to devise a simple yet near-optimal power allocation heuristic.

This paper presents an investigation of the energy-efficiency of two major cooperative diversity techniques in short-range wireless sensor networks: virtual-MISO (multiple-input-single-output) and decode-and-forward. The total energy consumption of a cooperative system consists of the transmission energy, the transceiver circuit energy and the local communication energy cost. In virtual-MISO explicit local communication precedes the long-haul cooperative transmission, whereas in decode-and-forward nodes cooperate by overhearing and repeating each other's long-haul transmissions. Our energy analysis shows that decode-and-forward is overall the more energy-efficient cooperative scheme. We also show that cooperation can yield large energy savings compared to traditional SISO (single-input-single-output) communication, even when the local distance between cooperating nodes is increased and becomes comparable to the long-haul distance. Given specific local and long-haul distance ranges, we formulate the recommended cooperation strategy in terms of the number of cooperating partners to employ for optimal energy-efficiency.

Cognitive radio (CR) is viewed as a possible solution to the problem of radio spectrum congestion. The CR technique utilizes a temporarily unoccupied licensed band. Before investigating the technical and political implications of CR, it is necessary to know to what extent the licensed bands are temporally unoccupied. This paper describes a spectral occupancy measurement campaign conducted in the frequency range between 806 MHz and 2750 MHz in urban Auckland, New Zealand. The purpose of the measurement is to identify potential spectral opportunities for CR. Statistical analysis of the measurement results are presented in the form of noise distributions, signal amplitude probability distributions, and spectral occupancy rates as percentages of time. These analyses indicate that, on average, the actual spectral usage in this band is only about 6.2%. Pint-to-point links and some mobile uplink channels are identified as the most probable candidates for future CR operations. These results suggest that CR could bring significant gains in spectral usage. These results also imply that, in order to provide a reliable detection of the primary signal, cooperative sensing techniques may be necessary to mitigate various wireless channel effects.

Effective antenna selection and deployment strategies are important for reducing co-channel interference in indoor wireless systems. Low-cost solutions are essential, and strategies that utilise simple (passive) antennas (such as directional patches) are advantageous from this perspective. However, performance is always an issue and the improvements achievable through clever antenna deployment (both placement and orientation) need to be quantified. An experimental investigation of indoor propagation comparing the performance of directional and omni-directional antennas is reported. In the case study of a voice-based indoor communication system employing DS-CDMA radio access technique with BPSK modulation, the outage probability for base stations fitted with directional antennas was observed to change in the −54% to +66% range relative to the omni-directional case. The effective change in the distribution of carrier-to-interference ratios by the use of directional antennas is well established in outdoor micro cellular deployment scenarios; however, the magnitude of the influence is quantified for an indoor environment in this case study. It is also shown that obstacles in the environment can amplify the effectiveness of the antenna deployment by acting as physical cell boundaries that restrict interference. External interference has been shown to cause a significant degradation to the performance of an indoor system when the carrier-to-external-interference ratio. This performance degradation can be minimised by appropriate deployment of directional antennas at the base stations, although the optimum antenna orientations depends on the strength of external interference.

Cochannel interference in indoor wireless communication systems can severely limit system capacity and performance. To reduce cochannel interference in indoor environments, electromagnetic shielding can be used to increase the radio isolation between physically adjacent systems. In this paper, the impact of structural (wall) shielding on the system performance of an interference-limited CDMA system is examined using a ray-tracing propagation model. A logarithmic relationship is observed between the average outage probability and the extent of shielding in a typical single-floor office environment. With an efficient deployment of shielding, the results obtained suggest that both the capacity and signal quality of a wireless system can be enhanced as the number of base stations increases. By incorporating shielding into the architecture of a building, wireless-friendly environments that facilitate better use of the available radio spectrum might be realized

Future wireless systems will need to support multirate traffic. The distribution of traffic influences both the optimal placement of base stations and consequently the system performance. In this paper, we propose a novel approach to solve the multirate-traffic CDMA base station placement problem using a standard binary integer programming (BIP) solver. This approach allows the designer to find optimal base station configurations for a multi-code (MC) CDMA system with the consideration of traffic demand of users, coverage, transmitter power limits and signal-to-interference (SIR) performance. Furthermore, the model can be modified to find the optimal code allocation to the users in an existing system. With the advancement in computing power, proposed model can potentially be used to design practical systems

One of the limitations of IEEE 802.11b DCF protocol is the low bandwidth utilization in the medium-to-high traffic load conditions, and consequently, it achieves low throughput and high mean packet delay. In this paper we propose an extension of the IEEE 802.11b DCF protocol called the buffer unit multiple access (BUMA) protocol that overcomes these shortcoming of the original IEEE 802.11 protocol. The proposed BUMA scheme achieves higher throughput (up to 35%) and lower mean packet delay (up to 87%) than the IEEE 802.11b DCF protocol at medium-to-high traffic load conditions. In this paper the BUMA scheme is described and simulation results are presented to verify the performance

Improving the reliability and coverage of indoor wireless systems is an important design goal. A highly reflective ceiling creates an elevated image of the access point, which delivers a strong and reliable multipath component to the mobile terminal. Measurement results show that a small area of metallic ceiling above the transmitter can provide significant enhancement to the received signal power across a large room. Experiments with human bodies obstructing the line-of-sight path were performed to further examine the effectiveness of such an architectural modification. The improvement can be as high as 6.5 dB in cases where the line-of-sight path is obstructed by a human body. Moreover, the effectiveness of the metallic ceiling does not diminish with the distance from the transmitter. A comparison of measured and simulated results shows that ray tracing simulation can adequately approximate the results observed by measurement at 5.8 GHz.

In this paper, the performance of a CDMA mobile radio system is analyzed under different traffic loads. The major influential parameters are identified and their effect on traffic capacity is analyzed using a simulation model. New results have been obtained by analyzing the sensitivity of Erlang capacity to a range of CDMA network parameters namely call quality, shadowing, distance exponent, voice activity, and processing gain. Comparison of the results indicate that the most influential parameter is call quality while shadowing followed by the processing gain have the least effect. It is noted that when the offered load is low for the system under study, a change of a few Erlang in the offered traffic has insignificant effect on the blocking probability. As the traffic increases, and the call quality drops below an adequate threshold, there is a sudden increase in the sensitivity of the blocking probability to traffic load.

In a general wireless system, cells are loosely defined and user signals appear at multiple antennas with various powers and delays. Despite the enormous performance benefits of system-wide maximum-likelihood multiuser detection (ML MUD), its application to such systems is hampered by the lack of a regular structure. Prior work usually dismisses the possibility on computational grounds as exponential in the total number of users, at least. This paper is the first to address efficient computation of system-wide ML MUD. We present a computational organization that achieves dramatic reduction in complexity through exploitation of the partial overlap of user sets at different antennas. This algorithm, which applies to code-division multiple access or narrowband systems, can be viewed as a spatio-temporal extension of the well-known Viterbi algorithm (VA), and, like the VA, it is derived from dynamic programming principles.

The authors present a performance analysis for the reverse link of a wireless DS-code division multiple access (CDMA) system that exploits macrodiversity reception while adopting the maximum likelihood (ML) multiuser detector for the basic detection. This appears to be the first analytical treatment of the ML multiuser macrodiversity detector in asynchronous DS-CDMA systems. They also include the effects of frequency selective fading, imperfect synchronization, and imperfect channel state information. Power control and connection control companion algorithms are presented to assess the value of this detector in a system context. The authors have shown that the ML multiuser-macrodiversity detector is capable of reducing the bit-error rate for many users by several orders of magnitude compared with multiuser detectors that operate on each antenna separately.

This paper examines the impact of a traffic stream's statistical properties on the propagation dependent performance of a CDMA system. Traffic in a CDMA system directly affects the amount of interference in the wireless channel and therefore the level of traffic corruption. We evaluate a typical outdoor 3G CDMA cellular deployment. System performance is compared using three diverse traffic types with a variety of propagation conditions and system configurations. It is shown that propagation dependent performance is generally insensitive to the statistical properties of the traffic stream. Only with non-hostile propagation conditions and low traffic loads is there a significant performance difference, in which case the more variable traffic results in inferior performance. This suggests that accurate traffic modeling is generally not necessary when dimensioning the propagation aspects of a CDMA system. A simplistic and convenient traffic model will usually be sufficient.

This article presents a new computational tool for use in general fading channel analysis when the detection scheme can be expressed as a quadratic form in zero-mean complex Gaussian random variables. We develop a simple numerical algorithm which is capable of inverting a characteristic function consisting of both simple and multiple poles. The approach benefits from the inherent symmetry in the residue calculations and uses the well-known Vandermonde matrix in order to take advantage of this symmetry. It is numerically stable, eliminates singularities, and circumvents the need for differentiation.

The combination of macrodiversity reception with maximum likelihood (ML) multiuser detection has the capability to reduce the bit error rate (BER) for many users by several orders of magnitude compared with multiuser detectors that operate on each antenna separately. In this paper, we present the conditional metric merge (CMM) algorithm which reduces the computational complexity of the ML multiuser-macrodiversity detector by an enormous factor. The CMM algorithm can be viewed as a spatial variant of the Viterbi algorithm. It is a new algorithm and is the first of its kind as ML multiuser-macrodiversity detection (MUMD) is a relatively new area of research.

A study is made of the problem of placing base stations to yield high capacity and efficiency in an in-building direct-sequence code-division multiple-access wireless communication system. A key requirement for solving this problem is a reliable but simple model of in-building propagation. A number of propagation models are considered as part of a system's performance analysis and are found to produce widely ranging levels of accuracy. Correlated shadowing is identified as being a 'key'in-building propagation characteristic that has the potential to strongly influence the system's performance. Propagation models that included correlated shadowing are shown to produce the most accurate estimates of outage probability when there are a number of interferers facing a user. Base station deployment is shown to be a dominant factor influencing the levels of correlated shadowing, and consequently, base station deployment is shown to have major implications on the system's performance. The system's performance for a variety of base station deployment strategies has been determined. The results indicate that there is a tradeoff between system simplicity and performance.

In tomorrow's wireless communications systems it is envisaged that users will be able to roam freely throughout a building while transferring information via a range of electronic technologies. To achieve this objective, knowledge of the indoor propagation environment is required. The effects that floors and walls have on system performance and efficiency are investigated. Comparisons of system performance are made using outage probability and a measure of spectral efficiency. It is shown that floors and walls can obstruct the propagation path of the indoor channel sufficiently to enable efficient system design.>

The design of tomorrow's mobile communications systems will require accurate mathematical tools for estimating the performance of potential system configurations. Ideally these tools will be easy to apply and be based upon parameters that can be estimated by a simple appraisal of the propagation environment. In this paper a general outage probability technique for considering the effect of noise and cochannel interference on reception reliability is presented. The technique is used to assess the compatibility and applicability of previously published techniques as that either treat noise as cochannel interference or consider a minimum detectable received signal threshold. A simple yet accurate threshold-based technique is described and used to predict bit error rates (BER) for a variety of conditions. Specifically, outage probability is used to accurately predict average BER.>

A statistical method for evaluating the performance measures of the base to mobile link of a multiple-cell CDMA system is presented. Specifically, techniques and expressions for estimating the short term average bit-error-rate (BER), service reliability and link availability are developed. The link performance is estimated for a mobile at the vertex of multiple adjacent cells. In the analysis, the system is assumed to employ coherent BPSK modulation and direct sequence spreading and the received signals are assumed to undergo Rayleigh fading, log-normal shadowing and frequency selective fading. The effects of power control and error correction are also investigated.>

Mobile radio systems are usually designed on the basis of providing adequate reception quality to a specified area. The outage probability equations are used to determine the quality of radio reception when that quality is limited by a minimum required signal level, interference from a cochannel transmitter, and variability in the received signal levels. Considering Rayleigh fading and lognormal shadowing as joint causes of signal variation, average outage probability expressions are derived for mobile radio systems of a uniform nature. These expressions are used to investigate the influence of various system and propagation characteristics on reception quality.>