Patent ID: 9107213
Filing Date: 2015-08-11
Classification: H04L,H04W

Abstract:
1. A method for including a tracking reference signal (TRS) in a downlink subframe, the method comprising: determining whether at least one of a time density or a frequency density of a channel-state-information reference signal (CSI-RS), included in the downlink subframe for at least one of time or frequency tracking by an user equipment, exceeds a threshold; generating, in response to determining that the at least one of the time density or the frequency density of the CSI-RS does not exceed the threshold, a TRS subframe by including the TRS in the downlink subframe at a frequency density of at least one resource element per six resource elements in the TRS subframe, the frequency density of the TRS in the downlink subframe configured for timing or frequency tracking by a user equipment, wherein generating the TRS subframe comprises configuring the TRS in the downlink subframe independently of the CSI-RS included in the downlink subframe; and transmitting the TRS subframe at a periodicity among other subframes not including the TRS.