Adaptive channel utilisation in IEEE 802.15.4 Wireless Body Sensor Networks: Adaptive Phase-Shifting Approach

A survey of IEEE 802.15.4 effective system parameters for wireless body sensor networks

“…This enables the coordinator to switch to the other channel at the exact time that the channel quality has degraded below the threshold [68]. A new study has shown that phase-shifting strategy can be effectively useful to improve the performance gain of WBSNs [69].…”

“…This enables the coordinator to switch to the other channel at the exact time that the channel quality has degraded below the threshold [68]. A new study has shown that phase-shifting strategy can be effectively useful to improve the performance gain of WBSNs [69]. 'Cognitive radio' (CR) networks provide the opportunity of sharing the same frequency spectrum with primary users of that particular frequency spectrum in an opportunistic manner.…”

“…Furthermore, a simulation study has been conducted to clarify the impacts of MAC parameters on WBSN's performance gain in the presence of intensifying internal interference. Internal interference in homogeneous Initial choice and idealised schemes (introduced as upper band) Castalia 3.2 simulator WBSNs and channel scarcity [66] Internal interference in homogeneous Greedy channel utilisation approach Castalia 3.2 simulator WBSNs and channel scarcity [67] Internal interference in homogeneous Continuous-hopping approach Castalia 3.2 simulator WBSNs and channel scarcity [68] Internal interference in homogeneous Continuous assessment versus periodic assessment Castalia 3.2 simulator WBSNs and channel scarcity [69] Internal interference in homogeneous Adaptive phase-shifting approach Castalia 3.2 simulator WBSNs and channel scarcity [70] Channel assignment problem Segment-based channel assignment strategy Analytical and simulation [71] Low performance gains due to channel Coexistence-aware spectrum sharing protocol Analytical and simulation coexistence [84] Low performance gains due to channel Coexistence detection and coexistence mitigation strategies OPNET simulator coexistence [85] Low performance gains due to channel DCM mechanism OPNET simulator coexistence [86] Low performance gains due to channel DCM mechanism Test-bed experiment (Markov model) coexistence [72] Low reliability and high delay due to Multi-channel MAC protocol approach internal interference [73] Destructive impacts of internal Advantages and disadvantages of various proposed multi-channel Analytical modelling (Markov model) interference on sensor network communication approaches performance gains [74] Increasing the nodes density and An energy-efficient multi-channel MAC protocol approach Test-bed experiments escalation of internal interference [76] Coexistence with other technologies Multi-radio prototype Test-bed experiment [77] Coexistence with other technologies Dynamic spectrum access strategy Test-bed experiment (Iris platform) [78] Performance degradation due to A low-power spectrum agile MAC protocol Analytical analysis and test-bed spectrum congestion caused by experiment (TelosB platform) increasing the popularity of wireless embedded devices [79] The current multi-channel MAC Dynamic multi-radio multi-channel MAC Test-bed experiment protocols are being inflexible to the variation of the environment [80] Performance degradation due to radio Coordinated channel switching and spectral multiplexing Test-bed experiment (Mica2 sensor nodes) interference [82] Channel scarcity Scheduler using throughput estimation and nearest vacancy ns_2 search [83] Internal interference Dynamic channel ...…”

Mitigation of mutual interference in IEEE 802.15.4-based wireless body sensor networks deployed in e-health monitoring systems

“…"Frequency-adaptation" approach [21] and [17] in a static environment has improved the reliability of data packet transmission in the presence of both external and mutual types of interference. In the follow-up research [19] "Adaptive Phase-shifting" scheme has been proposed, and its performance was evaluated against IEEE 802.15.4 standard in an ever-changing environment. However, its higher level of complexity is considered as a major limitation, even though deployment of this scheme resulted in significant improvement compared to the frequency-adaptation schemes in isolation.…”

“…Dynamic Phase Shifting scheme: This scheme is completely distributed randomly, and the need to obtain a global consensus (, e.g. agreeing on the number of occupants in each operating frequency [19] and [15]) is eliminated. The DPS scheme mainly runs two procedures in parallel with insignificant interaction between them, namely: frequency adaptation and phase adaptation.…”