Patent ID: 8295323
Filing Date: 2012-10-23
Classification: H04B

Abstract:
1. A method for synchronization of transmitted and received signals in frequency hopping communication systems where data is transmitted in frames comprising a preamble and a data block, the frequency hopping communication system comprising a transmitter and a receiver, two PN-generators, one located at a transmitting end and one located at a receiving end, both generating a same predefined frequency pattern causing the transmitter and the receiver to hop in frequency according to the same predefined frequency pattern, the receiver and the PN-generator at the receiving end also being part of a synchronization unit, the method comprising: slowing a clock rate in the receiver with respect to a clock rate of the transmitter, thus causing receiving the predefined frequency pattern of the transmitted signal in the receiver with a first delay proportional to a distance between the receiver and transmitter, wherein the characteristic pattern starts at a synchronization point in the interference pattern at the time tc after a second delay, wherein a Vernier scale effect causes the second delay, and wherein the second delay is a measure of the delay between the transmitted and received signal, to be magnified compared to the first delay.