Scrutinizing Bit- and Symbol-Errors of IEEE 802.15.4 Communication in Industrial Environments

Abstract

The knowledge of error nature in wireless channels is an essential constituent of efficient communication protocol design. To this end, this paper is the first comprehensive bitand symbol-level analysis of IEEE 802.15.4 transmission errors in industrial environments. The intention with this paper is to extract the error properties relevant for future improvements of wireless communication reliability and coexistence of radio systems in these harsh conditions. An extensive set of bit-error traces was collected in a variety of scenarios and industrial environments, showing that error behavior is highly dependent on the cause of packet corruption. It is shown that errors inflicted by multipath fading and attenuation exhibit different properties than those imposed by IEEE 802.11 interference. The statistical behavior of these two patterns is concurrently investigated in terms of differences in bit-error distribution, error burst length, channel memory length, and the scale of packet corruption. With these conclusions at hand, abiding to the computational constraints of embedded sensors and the statistical properties of bit-errors, a Reed-Solomon (15,k) block code is chosen to investigate the implications of bit-error nature on practical aspects of channel coding and interleaving. This paper is concluded by a number of findings of high practical relevance, concerning the optimal type, depth, and meaningfulness of interleaving.Index Terms-Error patterns, forward error correction (FEC), IEEE 802.15.4, industrial wireless sensor network (WSN), interleaving.

Embracing Corruption Burstiness: Fast Error Recovery for ZigBee under Wi-Fi Interference

“…Similar with [16], [24], we allow up to one correct byte inside a corruption burst Due to this requirement, existing works choose to use RS/BCH codes instead of XOR code, despite XOR code is much more lightweight.…”

“…Recent study [16] shows that the in-packet RSSI values are highly correlated with byte errors. We record the in-packet RSSI values and the corrupted positions to study the correlation.…”

“…In order to exploit the correlation between RSSI and byte errors, we should first measure RSSI samples while receiving a packet. By using a 32.5kHz timer in IRS (supported by most low power platforms ), we are able to obtain one RSSI value in per byte granularity [9], [16], enabling the identification of byte-level errors. We implement such a highresolution sampling procedure (i.e., at least one sample per byte) without extra hardware.…”

“…When certain levels of bit errors occur, the receiver can recover the original packet without retransmission. Recent studies have observed that ZigBee corruptions under Wi-Fi interference are highly bursty [11], [14]- [16]. The burstiness leads to the case that some blocks may be full of bit errors which cannot be recovered by the FEC, while other blocks may have no bit errors at all but still require redundant bits.…”

Survey of Energy Harvesting Systems for Wireless Sensor Networks in Environmental Monitoring

“…WSNs can be found in medical applications, such as cardiac monitoring and acquisition of ECG signals [1,2], monitoring structures, buildings [3] and industrial processes [4,5]. WSNs support logistic and transport processes [6,7], as well as military actions [8].…”