In this paper we consider the problem of estimating the propagation delays and relative amplitudes of the transmitted signals as well as detecting the data bits in an asynchronous direct-sequence code division multiple access (DS-CDMA) system operating over a fading channel. A subspace based estimator is proposed for estimating the propagation delays. The path gains and data bits are estimated ...

In this paper, we devise a new subspace method for estimating the di erential time delay of a signal received at two separated sensors as well as the frequencies of the source signal, assuming that it consists of multiple sinusoids. The time delay and frequency estimates are related to the eigenvalues and eigenvectors of a matrix obtained from the covariances of the received signals. The e ecti...

| In this paper we consider an asyn-chronous direct-sequence code division multiple access (DS-CDMA) communication system operating over an AWGN channel. In certain applications , the near-far problem can be the limiting factor for the capacity of a DS-CDMA system. Several near-far resistant receivers have therefore been proposed (e.g., the decorrelat-ing receiver). These receivers assume perfe...

In this paper we discuss delay estimation in time-delay systems. In the Introduction a short overview is given of some existing estimation techniques as well as identifiability studies. In the following sections we propose several algorithms for the delay identification based on variable structure observers.

Table 1: The TAG table for a two-input AND gate. cir-unit delay uit power estimation run time % speed ss tp err. ss tp up s349 265. Run-time under a unit delay model: ss : using symbolic simulation, tp : using transition probability. cir-fixed binary inertial delay uit power estimation run time % speed ss tp err. ss tp up s349 231.

The SLS and RLS estimation methods proposed for average power estimation are linear, unbiased, and do not assume any distribution for the input sample data. The experimental results indicate that the least square estimation algorithms converge up to 24 times faster than the Monte Carlo and DIPE for random inputs. ACKNOWLEDGMENT The authors would like to thank the reviewers and the associate edi...

Abstract : A popular technique for time delay estimation is to use an FIR filter to model the time difference and the filter weights are interpolated with a sinc function to obtain the delay estimate. However, the sinc interpolator requires a sufficiently long filter length for accurate delay estimation. In this paper, we propose to process the filter weights via a least squares based method in...

In this paper a new modified Cramer-Rao lower bound (MCRLB) for multipath time-delay estimation is developed for DS-CDMA systems. The lower variance bound of each estimated path delay is determined via computer simulations using the theoretical results, and it is compared with an efficient and practical delay estimation method, namely peak tracking with pulse subtraction. Simulation results sho...