Positioning of Wireless Devices

摘要

A method performed by a network node (10) for finding a direction to a wireless device (20) in a wireless communication network is provided. The method comprises the step (S1) of the network node transmitting reference signal pairs on at least one pair of correlated antennas. Each reference signal pair has a unique phase difference between the signals in the signal pair, and the unique phase differences of the reference signal pairs are distributed over a given angular interval. The method further comprises the step (S2) of the network node receiving from the wireless device, in response to each pair of reference signals, a respective indication of a preferred pre-coding matrix, and the step (S3) of the network node determining a direction to the wireless device based on the received indications, information representative of the phase differences of the reference signal pairs, and phase information related to the indicated preferred pre-coding matrices.

主权项

1. A method performed by a network node for finding a direction to a wireless device in a wireless communication network, a set of predefined precoders usable by the network node for user communication being known by both said network node and said wireless device, each precoder being defined by an individual pre-coding matrix, wherein said method comprises the steps of:
said network node transmitting a plurality of pairs of reference signals on at least one pair of correlated antennas, each pair of correlated antennas comprising a first and a second antenna, and each pair of reference signals comprising a first and a second reference signal and having its own unique phase difference between said first and said second reference signal, said first reference signal being transmitted on said first antenna and said second reference signal being transmitted on said second antenna, wherein the unique phase differences of said plurality of pairs of reference signals are distributed over a given angular interval; said network node receiving from said wireless device, in response to each pair of reference signals transmitted with its own unique phase difference, a respective indication of a preferred pre-coding matrix; and said network node determining a direction to said wireless device based on the received indications, information representative of at least part of the phase differences of said plurality of pairs of reference signals, and precoder-related phase information representative of differences in phase between the antennas for at least part of the indicated preferred pre-coding matrices.