Narrow-Band Interference Suppression in Spread-Spectrum CDMA Communications Using Pipelined Recurrent Neural Networks
نویسندگان
چکیده
This paper investigates the application of pipelined recurrent neural networks (PRNN’s) to the narrow-band interference (NBI) suppression over spread-spectrum (SS) code-division multiple-access (CDMA) channels in the presence of additive white Gaussian noise (AWGN) plus non-Gaussian observation noise. Optimal detectors and receivers for such channels are no longer linear. A PRNN that consists of a number of simpler small-scale recurrent neural network (RNN) modules with less computational complexity is conducted to introduce best nonlinear approximation capability into the minimum mean-squared error nonlinear predictor model in order to accurately predict the NBI signal based on adaptive learning for each module from previous non-Gaussian observations. Once the prediction of the NBI signal is obtained, a resulting signal is computed by subtracting the estimate from the received signal. Thus, the effect of the NBI can be reduced. Moreover, since those modules of a PRNN can be performed simultaneously in a pipelined parallelism fashion, this would lead to a significant improvement in its total computational efficiency. Simulation results show that PRNN-based NBI rejection provides a superior signal-to-noise ratio (SNR) improvement relative to the conventional adaptive nonlinear approximate conditional mean (ACM) filters, especially when the channel statistics and exact number of CDMA users are not known to those receivers.
منابع مشابه
Narrow-band interference suppression in wavelet packets based multicarrier multicode CDMA overlay system
The wavelet packets based multicarrier (MC) multicode (MCD) code-division multiple-access (CDMA) transceiver consists of the MCD part, which ensures the transmission for high speed and flexible data rate; the MC part contributing to robustness to frequency-selective fading and flexibility for handling multiple data rates; and wavelet packets (WPs) modulation technique, which contributes to the ...
متن کاملNarrow-Band Interference Suppression in CDMA Spread-Spectrum Communication Systems Based on Sub-Optimum Unitary Transforms
In this paper, we present several unitary transform-domain filtering techniques based on KarhaunenLoeve Transform (KLT) for narrow-band interference rejection in CDMA communication systems. The reason for selecting the KLT is that it is an optimum unitary transform in the sense of packing the energy of the narrow-band interference. As a result after applying this transform, a small portion of t...
متن کاملNarrowband Interference Suppression in Spread Spectrum Cdma Channel Data Noisy Data Pn Sequence Pn Sequence Figure 1: Spreading/despreading Procedure
Narrowband Interference Suppression in Spread Spectrum CDMA H. Vincent Poor, Leslie A. Rusch Code-division multiple-access (CDMA) implemented with direct-sequence spread spectrum signaling is among the most promising multiplexing technologies for cellular telecommunications services, such as personal communications, mobile telephony, and indoor wireless networks [1, 2, 3, 4, 5]. The advantages ...
متن کاملCode-Aided Interference Suppression for DS/CDMA Overlay Systems
The push toward more efficient and flexible use of the radio spectrum has led to the consideration of the overlay of spread-spectrum (SS) communication networks on preexisting narrow-band networks. Such systems are already in widespread and rapidly expanding use in the lightly regulated spectrum where personal networking is largely centered and they are of increasing interest in the more tightl...
متن کاملIntelligent CDMA systems
Direct-sequence Code-division multiple-access (DS-CDMA) has emerged as proper format for communication systems. As a result of multiple-access interference (MAI), inter-symbol interference (ISI), narrowband interference (NBI) and nonlinearities in channels, DS-CDMA systems can suffer deterioration in performance . New techniques to suppress narrow-band and multiple-access interference for sprea...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1999