Time-synchronised multi-piconet Bluetooth environments

Multiple Bluetooth piconets operating in the globally available 2.4 GHz industrial, scientific and medical (ISM) band are likely to co-exist in a physical environment, supporting applications such as wireless earphones, keyboards etc. An independently operating Bluetooth piconet will inevitably encounter the interference from collocated piconets, which results in both individual piconet and overall network performance degradation. We propose a simple time-synchronisation scheme among co-existing Bluetooth piconets that yields considerable performance improvements as compared to uncoordinated piconets. We introduce a new state to the Bluetooth link controller that does not require any changes to the existing Bluetooth hardware. The proposed scheme synchronises the collocated piconets in a totally blind fashion and incurs minimal overhead to the participating piconets. The performance of the scheme is measured by evaluating metrics such as packet error rate, individual piconet throughput and aggregate network throughput using an extensive analytical model. Furthermore, the effect of partial synchronisation among collocated piconets is also investigated.