Patent ID: 8976765
Filing Date: 2015-03-10
Classification: H04J,H04L,H04W

Abstract:
1. A method comprising: a) transmitting, by a base station in a plurality of base stations, at least one first control message to a wireless device, said at least one first control message configured to cause in said wireless device: b) transmitting, by said base station, a plurality of timing advance commands to said wireless device, each of said plurality of timing advance commands comprising: wherein: i) frames and subframes transmission timing for downlink carriers in said primary cell group and downlink carriers in said secondary cell group are substantially time aligned with each other; ii) frames and subframes transmission timing for downlink carriers in said primary cell group and downlink carriers in said secondary cell group of said base station are substantially time aligned with frames and subframes transmission timing of downlink carriers of other base stations in said plurality of base stations; iii) frames and subframes transmission timing for uplink carriers in said primary cell group of said wireless device are substantially time aligned with each other; iv) frames and subframes transmission timing for uplink carriers in said secondary cell group of said wireless device are substantially time aligned with each other; v) frames and subframes transmission timing for uplink carriers in said primary cell group and in said secondary cell group of said wireless device employ: vi) said plurality of timing advance commands are configured to cause said wireless device to adjust timing of uplink signal transmissions in uplink carriers of said primary cell group and said secondary cell group such that said base station receives said uplink signal transmissions in substantial alignment with frames and subframes of said base station; and wherein frame and subframe timings are substantially aligned when said frame and subframe timings are aligned within an accuracy limit.