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An investigation of RAKE receiver operation in an urban environment for various spreading bandwidth allocations

The renewed interest in the application of the spread-spectrum techniques such as CDMA to cellular mobile radio systems, in both the US, and within Europe through the RACE II and UK DTI/SERC LINK programs continues to gather momentum. To this end, an analytical performance model has been developed in order to provide a greater insight into the operation of this technique, in particular the sensitivity of the bandwidth efficiency of the network to the form of diversity signal processing used in the mobile transceiver. This theme is continued with an investigation of the wideband channel characteristics of an urban service area. Results are presented relating the statistics of the RAKE receiver branches to the spreading bandwidth used.<<ETX>>

An evaluation of direct sequence CDMA for future mobile communication networks

The performance and some of the implementation aspects of a practical mobile radio communications network employing direct-sequence code-division multiple access (DS-CDMA) are examined. The use of spread-spectrum techniques results in a wideband system, thus permitting the potential exploitation of multipath signal energy and permitting a means of reducing interference arising from other users of the spectrum. An analytical performance model is developed in order to assess the spectral efficiency of a DS-CDMA communications network. The computer model permits the performance evaluation of various path diversity schemes alongside numerous digital-modulation and error-correction coding techniques while operating in a mobile radio channel. In order to substantiate the results presented, novel power control and handoff protocols are also proposed in light of the assumptions made.<<ETX>>

On the optimum DS-CDMA channel bandwidth for personal communication systems

The authors discuss some of the issues concerning the optimum spread spectrum bandwidth for use in proposed third-generation direct sequence code division multiple access (DS-CDMA) systems, such as the European Universal Mobile Telecommunications System (UMTS), based upon recent system-specific wideband channel sounding measurements in the city of Bristol combined with results from computer simulation of a RAKE receiver architecture.

A Comparison Of Maximal Ratio And Equal Gain Diversity Combining In Direct Sequence CDMA Future Mobile Communication

An analytical performance model is presented which assesses the spectral efficiency of a DS-GDMA communications network. The computer model permits the performance evaluation of various path diversity schemes alongside numerous digital modulation and error correction coding techniques, whilst operating in a mobile radio channel.