支持移动锚节点的无线电干涉测距信号设计

为了使无线电干涉定位系统(RIPS)支持移动锚节点在发射测距信号的同时将自身变化的位置信息广播出去,提出使用二进制频移键控(BFSK)信号代替原单音信号作为新的测距信号。设计了新信号参数,可以从新信号相位中提取节点间的距离信息。提出了基于解调数据辅助的最大似然估计法,用于BFSK信号的相位估计。通过仿真可以得到在中高信噪比时,所提估计方法能够达到克拉美罗界,且相比无解调数据辅助的方法,在达到相同性能时可节省约3dB的信号功率。结果表明,使用BFSK信号时,RIPS可以应用于含有移动锚节点的传感器网络节点定位中。

Ranging signal design for radio interferometric positioning systems supporting mobile anchor nodes

To ensure radio interferometric positioning systems (RIPS) supporting Mobile anchor nodes to transimit ranging information while broadcasting their varying positions information simultaneously, the binary frequency shift keying(BFSK)-modulated signal was suggested to use instead of the single tone as the new ranging signal. The parameters of the new signal were analyzed and designed, so that the distance information between nodes can be extracted from the phase of the signal. A new method was designed for the phase estimation of the BFSK signal: data assisted maximum likelihood estimation (DAMLE). Simulation results show that the DAMLE method can reach the Cramer-Rao bound and spares 3 dB signal power compared with the method without data assisted with median and high signal-to-noise ratio. RIPS which use the new ranging signal can support mobile anchor nodes.