Burst Error Probability Research Articles

Robust Analog Beamforming for Periodic Broadcast V2V Communication

We generalize an existing low-cost analog signal processing concept that takes advantage of the periodicity of vehicle-to-vehicle broadcast service to the transmitter side. In particular, we propose to process multiple antennas using either an analog beamforming network (ABN) of phase shifters, or an antenna switching network (ASN) that periodically alternates between the available antennas, to transmit periodic messages to receivers that have an analog combining network (ACN) of phase shifters, which has been proposed in earlier work. To guarantee robustness, we aim to minimize the burst error probability for the worst receiving vehicular user, in a scenario of bad propagation condition that is modeled by a single dominant path between the communicating vehicles. In absence of any form of channel knowledge, we analytically derive the optimal parameters of both ABN and ASN. The ABN beamforming vector is found to be optimal for all users and not only for the worst receiving user. Further, we demonstrate that Alamouti scheme for the special case of two transmit antennas yields similar performance to ABN and ASN. At last, we show that the derived parameters of the two proposed transmission strategies are also optimal when hybrid ACN-maximal ratio combining is used at the receiver.

Performance of Optical Node for Optical Burst Switching

Optical Burst Switching (OBS) is a switching paradigm that offers very high throughput with reasonable delay. In OBS, data is transported in the form of the optical burst of unknown length. Till date, the size of the burst can't be estimated in advance. Hence, in OBS deflection routing, contending burst is deflected to some other node and after some more slot, it will re-appear on the same node. This mechanism is known as deflection of burst. In our previous work, an estimation of burst is done and optical node architecture is used to store optical burst. The buffering of burst will reduce average latency as well as improve Burst Error Probability (BER). In this paper, the performance evaluation of the node architecture is presented under various conditions and it is shown that deflection routing along with buffering of contending burst provide very effective solution.

Space diversity reception and parallel blind equalization in short-burst TDMA systems

We consider a q-antenna space diversity system combined with two parallel equalizer branches for the reception of short-burst time-division multiple-access signals. By applying a combination of several previously proposed blind equalization algorithms, we make significant improvements over the burst error probability performance reported to date. This is achieved by starting the two blind equalizers from different initial tap settings and applying a specific weighting of the equalizers' outputs in order to derive the symbol decision. A burst error probability of less than 10/sup -3/ is achieved with the new strategy for a root mean square (rms) delay spread of less than 0.4 times the symbol duration.

Tighter bounds on the error probability of fixed convolutional codes

We introduce new upper bounds for the bit and burst error probabilities, when a convolutional code is used for transmission over a binary input, additive white Gaussian noise (AWGN) channel, and the decoder performs maximum-likelihood decoding. The bounds are tighter than existing bounds, and nontrivial also for signal-to-noise ratios below the computational cutoff rate.

New Decoding Error Probability Bounds for Fixed Convolutional Codes used in BSC

Abstract New upper bounds for the bit and burst error probabilities are derived for the case, when a fixed convolutional code is used for communication over the binary symmetric channel (BSC) and the decoder performs maximum likelihood decoding. These bounds are tighter than existing bounds.

Performance and error propagation of two DFE channels

We compare performance and error propagation of DFE with and without a d=1 RLL code, at 2.67 user density and with a single coefficient FIR phase equalizer. Performance without error propagation is slightly better with d=1 in spite of the rate loss, because precursor ISI can be completely eliminated. We develop a model to estimate the effects of error propagation for both d=0 and d=1. The model is in good agreement with a 20 db SNR simulation. For an overall error rate of 10/sup -6/, the probability of a burst of length 50 in the decoded data is 10/sup -13/ for d=1 and 10/sup -8/ for d=0. This large difference is due both to the higher code rate and to the larger postcursor cancellation for d=0. In the model, we rigorously compute burst error probabilities using a Markov chain derived from our channel assumptions. We also use the model to compute the decay rate of the burst error probability and to identify the set of infinitely propagating sequences. In the simulations, we use random data and a commonly used (1,7) code for DFE17, to which we added AWGN noise at SNR 20 db. Finally, we compare the results of the model with the simulations.