Location system and wireless base station

Abstract

In the conventional wireless location system that synchronizes base stations by wireless communication, waveforms of a signal used for synchronization and of a signal used for delay measurement are the same, and therefore if there is a reflected wave in an earlier-sent signal, it becomes difficult to distinguish two kinds of signals, and accordingly location accuracy suffers degradation. Moreover, when two different waveforms are allocated to the two signals, a matched filter that supports the two waveforms becomes necessary, which inevitably makes a circuit size large. The invention is characterized in that signals having the same waveform but having different polarities are allocated to the synchronizing signal and the signal for delay measurement, respectively. This enables the two kinds of signals to be detected with one matched filter and also to be distinguished by simple means using polarity difference.

Description

technical field [0001] The present invention relates to a positioning system for measuring the position of a node having a wireless transmission function, and a wireless base station of the system. Background technique [0002] The so-called sensor network concept of "sending information collected by small sensor terminals (nodes) to the server through a wireless network" has become practical in recent years due to the development of circuit miniaturization technologies such as MEMS and the advent of new wireless communication methods. Advance greatly. [0003] These small sensor nodes that do not require wired connections are flexible in terms of installation and operation, but on the other hand, in order to identify the location where an abnormality occurs, a technology for measuring the position of the sensor is required. As a conventional node position measuring method, a representative method is a method of measuring positions using signals from satellites such as GPS....

AI Technical Summary

Problems solved by technology

[0005] In the prior art, since the signal used to calculate the delay from the node to the base station has the same waveform as the signal used for synchronization between the base stations, it is difficult to distinguish between the two signals when there is a reflected wave in the previously transmitted signal. Accuracy deterioration

In addition, when assigning different waveforms to two signals, a matched filter (MF) corresponding to the two waveforms is required on the receiving side, so there is a problem that the circuit scale increases

Images