In this paper, we propose to use a new nonparametric noncoherent detector for PN code acquisition in DS/CDMA systems. Because this detector is nonparametric, we can decide the threshold of the detector without "rst having to estimate the variance of time-varying interference. We compare the single-dwell scheme using the proposed detector with that using the conventional detector. From the simul...

In this paper, a neural network based direct sequence spread spectrum code synchronization system is proposed. This system is based on training a recurrent random neural network (RNN) model on all the possible phases of the used spreading code. The trained network can then be used at the receiver for the initial coarse alignment of the local code phase and the received code. One advantage of th...

A noncoherent sequential P N code acquisition technique is proposed in this paper. Noncoherent detection is employed to handle the seriously noisy environments, while the carrier frequency offset and data modulation effects can be simultaneously taken care of. To realize the sequential acquisition, the out-of-phase and in-phase sequences are properly modeled to avoid the significantly high erro...

New differentially coherent detectors for acquisition of direct sequence spread-spectrum signals are introduced. These detectors are alternatives to the noncoherent detectors that have been considered almost exclusively in the past. The proposed detectors are suitable for commercial code-division multiple-access (CDMA) systems which operate with a relatively large noise floor and provide a surp...

This paper proposes a noncoherent hybrid parallel pseudonoise (PN) code acquisition scheme for code-division multiple access (CDMA) mobile communication systems and analyzes the e ect of multiple access interference (MAI) on the code acquisition performance for Rayleigh and Rician fading channels. The hybrid acquisition scheme combines parallel search with serial search to cover the whole uncer...

Cyber criminals may abuse open wireless networks or those with weak encryption for cyber crimes. Assume surveillance has identified suspect traffic such as child porn downloading traffic on the Internet. To locate such criminals, law enforcement has to first identify which mobile (MAC) is generating suspect traffic behind a wireless router. The challenge is how to correlate the private wireless...

In most previously reported studies on pseudonoise (PN) code acquisition, independent additive noises have been assumed in various noise environments. The use of an independent observation model may cause considerable performance degradation in modern high datarate communication systems. In these studies, only additive noise model is considered. In this paper, a new detector for PN code acquisi...

In direct-sequence spread-spectrum systems, successful communications require phase synchronization of the incoming pseudonoise (PN) coded waveform with a locally generated replica at the receiver. It has been previously shown that sequential PN code acquisition schemes have the potential to achieve the best performance, but they are the least analyzed because of the analytical difficulties. Th...