Estimation of the error performance objectives for satellite communication systems

Abstract

SUMMARYWe consider the physical layer error performance parameters and design criteria for digital satellite systems established by ITU-R Recommendation S.1062, where the performance objectives are given in terms of the bit error rate (BER) divided by the average number of errors within a cluster. It is well known that errors on satellite links employing forward error correction (FEC) schemes tend to occur in clusters. The resulting block error rate is the same as if it was caused by randomly occurring bit errors with an error-event ratio of BER/a, where a is the average number of errors within a cluster. The factor, a, accounts for the burstiness of the errors and also represents the ratio between the BER and the error-event ratio. This paper proposes theoretical methods to estimate the factor, a. Using the weight distributions of the FEC codes, we derive a set of expressions for the factor, a, as well as their compact lower bounds. We present lower bounds for various FEC schemes including binary BCH codes, block turbo codes, convolutional codes, and turbo codes. The simulation results show that the proposed lower bounds are good estimates in the high signalto-noise ratio region.

Standardization on performance objectives of satellite systems using adaptive coding and modulation

“…The required BER/ α values range from 10 −10 to 10 −4 depending on the bit rate and percentage of time. The purpose of using the design mask expressed in terms of BER/ α is to represent how the error events are distributed in time and thus express the throughput aspect as well . In addition, α values are determined not only by the channel characteristics but also by the employed FEC scheme.…”

“…For digital satellite systems, the adoption of a powerful FEC scheme, such as a turbo code or low density parity check (LDPC) code, is mandatory to compensate for the various channel losses. Extremely long codewords are used in turbo or LDPC codes compared to the other conventional FEC schemes, and this eventually will increase the value of α . Utilization of a powerful FEC scheme can both decrease BER and further reduce BER/ α due to an increase in α .…”

“…Extremely long codewords are used in turbo or LDPC codes compared to the other conventional FEC schemes, and this eventually will increase the value of . 5 Utilization of a powerful FEC scheme can both decrease BER and further reduce BER/ due to an increase in . Table 1 is an example of the performance objectives defined for the satellite system operating near a 155 Mbps bit rate, when = 10.…”