Patent ID: 8405543
Filing Date: 2013-03-26
Classification: G01S,H04B,H04W

Abstract:
1. A method for distance measurement between a first node and a second node of a radio network, the method comprising: transmitting a first signal with a first frequency by the first node that is received by the second node by downmixing to a first intermediate frequency; determining a first value of a first phase for a first frequency value of the first frequency by the second node; transmitting a second signal with a second frequency by the second node that is received by the first node by downmixing to a second intermediate frequency; measuring a first value of a second phase for a first frequency value of the second frequency by the first node, the first frequency and the second frequency being changed in that a second frequency value of the first frequency and the first frequency value of the first frequency have a frequency difference and in that a second frequency value of the second frequency and the first frequency value of the second frequency have the frequency difference; determining a second value of the first phase by the second node for the second frequency value of the first frequency; determining a second value of the second phase by the first node for the second frequency value of the second frequency, wherein an amount of the first and second intermediate frequency is the same; spacing apart the first frequency of the first signal and the second frequency of the second signal by the amount of the first and second intermediate frequency; and calculating a distance between the first node and the second node from the first value and the second value of the first phase and from the first value and the second value of the second phase and from the frequency difference.