| Detection methods for multiple rate Direct Sequence Code Division Multiple Access (DS-CDMA) signalling are addressed. Attention is focussed on the development of receivers based on the minimum mean squared error (MMSE). Due to the cyclostationarity of the mul-tirate signal, a representation of the multirate signal in terms of the Fourier basis is possible. This expansion facilitates construct...

This papers analyzes the particular requirements that multimedia communication imposes on the network adapter and on the I/O subsystem of a workstation. An adapter architecture is developed that is specially suited for multimedia communication. The key ideas are the separation of isochronous and asynchronous traffic and the execution of per-byte protocol operations on the adapter. The adapter d...

In this paper we characterize the user capacity i e the maximum number of supportable users at a common SIR target level for a xed processing gain of a single cell symbol asynchronous CDMA system Based on the delay pro le of the users we identify a class of optimum signature sequences that achieve a lower bound on the total squared asynchronous correlation TSAC among the users When the users si...

In non-cooperative scenarios, the spreading sequences or waveforms of direct sequence spread spectrum (DSSS) signals is unknown to receiver. This paper focuses on addressing problem blind estimation waveform under multipath channels. scenario signal path transmission, can be directly obtained based estimated waveforms. However, in presence channels, becomes convolution and channel response, thu...

The optimization between the processing gain and the theoretically achievable average channel capacity per user (in the Shannon sense) of a constant total system's allocated bandwidth hybrid direct sequence/fast frequency hopping codedivision multiple-access (DS/FFH-CDMA) cellular system, when operating in a Rayleigh fading environment, is presented. ... Pagination p 902-910 Subject Engineering...

Multiuser decision-feedback detectors (DFDs) for direct-sequence code-division multiple access, based on the minimum mean-squared error (MMSE) performance criterion, are described. Both successive and parallel feedback (interference cancellation) with hard decisions are considered. An iterative DFD is presented, which consists of cascaded DFDs, each performing successive cancellation. The two-s...

To accommodate high-speed data transmissions, it may be necessary to substantially reduce the processing gain of a direct-sequence spread-spectrum (DSSS) system. As a result, intersymbol interference effects may become more severe. In this paper, we present a new structure for maximum-likelihood sequence estimation equalization of DSSS signals on a multipath fading channel that performs the fun...

This letter contains two parts. In the first part, the probabilistic data association (PDA) method is extended to multiuser detection over symbol-asynchronous code-division multiple access (CDMA) communication channels. A direct extension as well as a sliding window processing method are introduced. While achieving near-optimal performance with ( ) computational complexity in synchronous CDMA, ...