In this paper, we propose a packet-interleaving scheme (PIS) for increasing packet reliability under burst errors in wireless sensor networks (WSN). In a WSN, packet errors could occur due to weak signal strength or i...In this paper, we propose a packet-interleaving scheme (PIS) for increasing packet reliability under burst errors in wireless sensor networks (WSN). In a WSN, packet errors could occur due to weak signal strength or interference. These erroneous packets have to be retransmitted, which will increase network load substantially. The proposed PIS, encoding data using Reed-Solomon (RS) codes, can classify data into two different types: high-reliability-required (HRR) data and non-HRR data. An HRR packet is encoded with a short RS symbol, while a non-HRR packet with a long RS symbol. When an HRR and a non-HRR packet arrive at a sensor, they are interleaved on a symbol-by-symbol basis. Thus, the effect of burst errors (BE) is dispersed and consequently the uncorrectable HRR packets can be reduced. For the purpose of evaluation, two models, the uniform bit-error model (UBEM) and the on-off bit-error model (OBEM), are built to analyze the packet uncorrectable probability. In the evaluation, we first change the lengths of BE, then we vary the shift positions in a BE period, and finally we increase the number of correctable symbols to observe the superiority of the proposed PIS in reducing packet uncorrectable probability.展开更多
In this paper a new approach for increasing the performance of burst error correction that occurs during data transmission in low-frequency channels with pulse-code modulation is proposed. The specific technique is ba...In this paper a new approach for increasing the performance of burst error correction that occurs during data transmission in low-frequency channels with pulse-code modulation is proposed. The specific technique is based on the weighted checksum which is computed with arithmetic operations. It is shown that the solution proposed not only guarantees the correction of any single error burst but it also lowers the computational complexity so that procedure correction time does not depend on controlled data block length. Finally, the use of the algorithm is illustrated via the thorough presentation of an example of erroneous data transmission.展开更多
Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate ...Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate in burst-mode,hence the turn-on effects in optical network units(ONUs)may introduce burst errors,which are difficult for LDPC to deal with.One of the solutions is introducing an interleaver to convert consecutive burst errors into separate random errors.The traditional interleavers such as the block interleaver and the random interleaver,only consider dispersing the consecutive errors.In this paper,we present a design methodology for channel-adaptive interleaving pattern by joint optimizing of interleaving and LDPC decoding in PON systems deploying LDPC codes.After determining the interleaving pattern where the bits can be recovered with more reliable messages during LDPC iterative decoding,we map the bits from the potential locations of burst errors to the interleaving positions.By doing so,we can not only disperse the burst errors but also make full use of the LDPC code to improve its decoding performance.The numerical results show that the proposed interleaving scheme has a better performance under any burst-error length.展开更多
文摘In this paper, we propose a packet-interleaving scheme (PIS) for increasing packet reliability under burst errors in wireless sensor networks (WSN). In a WSN, packet errors could occur due to weak signal strength or interference. These erroneous packets have to be retransmitted, which will increase network load substantially. The proposed PIS, encoding data using Reed-Solomon (RS) codes, can classify data into two different types: high-reliability-required (HRR) data and non-HRR data. An HRR packet is encoded with a short RS symbol, while a non-HRR packet with a long RS symbol. When an HRR and a non-HRR packet arrive at a sensor, they are interleaved on a symbol-by-symbol basis. Thus, the effect of burst errors (BE) is dispersed and consequently the uncorrectable HRR packets can be reduced. For the purpose of evaluation, two models, the uniform bit-error model (UBEM) and the on-off bit-error model (OBEM), are built to analyze the packet uncorrectable probability. In the evaluation, we first change the lengths of BE, then we vary the shift positions in a BE period, and finally we increase the number of correctable symbols to observe the superiority of the proposed PIS in reducing packet uncorrectable probability.
文摘In this paper a new approach for increasing the performance of burst error correction that occurs during data transmission in low-frequency channels with pulse-code modulation is proposed. The specific technique is based on the weighted checksum which is computed with arithmetic operations. It is shown that the solution proposed not only guarantees the correction of any single error burst but it also lowers the computational complexity so that procedure correction time does not depend on controlled data block length. Finally, the use of the algorithm is illustrated via the thorough presentation of an example of erroneous data transmission.
基金supported by National Natural Science Foundation of China(No.U21A20454).
文摘Recently,the NGPON2 standards organization has decided to deploy LDPC code in upstream and downstream channels in next-generation Ethernet passive optical network(NG-EPON)systems.However,PON upstream channels operate in burst-mode,hence the turn-on effects in optical network units(ONUs)may introduce burst errors,which are difficult for LDPC to deal with.One of the solutions is introducing an interleaver to convert consecutive burst errors into separate random errors.The traditional interleavers such as the block interleaver and the random interleaver,only consider dispersing the consecutive errors.In this paper,we present a design methodology for channel-adaptive interleaving pattern by joint optimizing of interleaving and LDPC decoding in PON systems deploying LDPC codes.After determining the interleaving pattern where the bits can be recovered with more reliable messages during LDPC iterative decoding,we map the bits from the potential locations of burst errors to the interleaving positions.By doing so,we can not only disperse the burst errors but also make full use of the LDPC code to improve its decoding performance.The numerical results show that the proposed interleaving scheme has a better performance under any burst-error length.