Robust detection of a weak signal with redescending M‐estimators: A comparative study

On finite samples redescending M‐estimators outperform linear bounded Huber's M‐estimators. To provide stable detection of a weak signal of arbitrary shape, robust Neyman–Pearson detection rules based on redescending M‐estimators of location are introduced and studied. It is shown that, on the whole, robust detectors based on redescending M‐estimators outperform conventional Huber's linear bounded detectors rules under light‐ and heavy‐tailed noise distributions both on large and small samples. Copyright © 2009 John Wiley & Sons, Ltd.     

Concatenated coding scheme for MTCM/CPFSK with Hamming code

An investigation into the burst statistics of multiple symbol trellis coded continuous phase frequency shift keying is presented. Based on this investigation, an outer linear block code with a block interleaver has been developed, and is presented to demonstrate the efficient correction of burst errors     

Performance of RCPC codes with soft-decision decoding overNakagami-m fading channels

The analytical upper bounds on the pairwise error probability of rate compatible punctured convolutional (RCPC) codes, using coherent BPSK signals over slow frequency nonselective Nakagami-m fading channels with AWGN, are evaluated. With perfect channel state information (CSI) assumption, we use a direct integral with the Nakagami-m probability density function to obtain a closed form upper bound. For the case without CSI, we find an approximated upper bound for the high SNR cases and the approximation can be justified for signal to noise ratio (SNR) E _s/N₀ ≫ 1.5 dB     

Transition probabilities of coded BPSK signals for hard-decisiondecoding with k-bit CSI in Nakagami-m fading channels

We evaluate a closed form expression of the transition probabilities used for calculating metric values and pairwise error probabilities of convolutional codes, equipped with coherent BPSK signals, for hard-decision decoding with k-bit channel state information (CSI) in slow varying frequency nonselective Nakagami-m fading channels. It is noted that 1-bit CSI is sufficient to take advantage of channel information under deep fadings     

Throughput analysis of bifurcated input-queued packet switches withrestricted contention

An input-queueing scheme is suggested in which a buffer is divided into several smaller buffer blocks for enhancement of the limited throughput of the ordinary input-queued switch. The scheme is analysed and compared with respect to the performance of the scheme with free contention     

Virtual circuit connection method for RSVP multicasting supportingheterogeneous receivers on the ATM network

The authors suggest a novel virtual circuit connection method based on the reverse traversing technique to minimise the waste of network bandwidth resources, when the Internet protocol multicast is interoperated using the resource reservation protocol over an asynchronous transfer mode network. Simulation results show that, as the number of receivers increases, the bandwidth requirements on all links of the network of the proposed scheme become more advantageous than those of other conventional methods     

Clock multiplier using digital CMOS standard cells for high-speeddigital communication systems

The authors propose and evaluate the performance of a 2^N times clock multiplier that controls memory components for high-speed data communications. To improve the reliability of the circuit, a symmetric circuit structure is used, while to verify circuit operation by means of a simple method, an MVU estimator is found from simulation data. The proposed circuit can provide clock rates, which are usually required in the multiple phase shift keying (MPSK) or multiple quadrature amplitude modulation (MQAM) modulation schemes, of 2 to 2^N times that of the input clock     

A new fusion formula and its application to continuous-time linear systems with multisensor environment

The problem of fusion of local estimates is considered. An optimal mean-square linear combination (fusion formula) of an arbitrary number of local vector estimates is derived. The derived result holds for all dynamic systems with measurements. In particular, for scalar uncorrelated local estimates, the fusion formula represents the well-known result in statistics. The fusion formula is applied to fusion of local Kalman estimates in multisensor filtering problem. Examples demonstrate high accuracy of the proposed fusion formula.     

Asymptotically stable detection of a weak signal

To design highly efficient and robust detectors of a weak signal, an asymptotic approach to stable estimation exploiting redescending score functions is used. Two new indicators of robustness of detection, the detection error sensitivity and detection stability, are introduced. The optimal Neyman–Pearson rules maximizing detection efficiency under the guaranteed level of detection stability are written out. Under heavy‐tailed noise distributions, the proposed asymptotically stable detectors based on redescending score functions, namely, the minimum error sensitivity and the radical ones, outperform conventional linear bounded Huber's and redescending Hampel's detectors both on small and large samples. Copyright © 2013 John Wiley & Sons, Ltd.     

Joint antenna subset selection for spatial multiplexing systems based on statistical and instantaneous selection criteria

While the joint transmit/receive (Tx/Rx) AnSS with exhaustive search is the best solution for error rate minimization, its complexity makes it difficult for implementation on practical systems. To overcome this disadvantage, we propose a two-stage AnSS algorithm for the spatial multiplexing (SM) in the multiple input multiple output (MIMO) system, which employs both the statistical (i.e., average Euclidean distance, AED) and instantaneous selection criteria (i.e., modified instantaneous Euclidean distance, M-IED). The proposed algorithm reduces the computational complexity by decoupling the joint Tx/Rx selection into two separate selections of the numbers of Tx/Rx antennas and antenna subset, respectively. We show that the proposed AED criterion can be implemented through a simple look up table (LUT), thereby significantly reducing the computational complexity. Simulation results and computational complexity comparisons, prove that the proposed two-stage AnSS algorithm for the SM scheme reduces the hardware and computational complexity without any loss of the signal-to-noise ratio (SNR) and the diversity order, compared to the exhaustive search method.