CPC H04B 1/7107 (2013.01) [H04B 17/345 (2015.01); H04L 1/0038 (2013.01); H04L 27/0012 (2013.01); H04W 4/70 (2018.02); H04W 52/242 (2013.01); H04W 52/243 (2013.01); H04W 52/367 (2013.01); H04W 52/383 (2013.01); H04W 72/02 (2013.01); H04W 72/0473 (2013.01); H04W 76/14 (2018.02); H04W 88/023 (2013.01); H04W 88/06 (2013.01); H04J 11/004 (2013.01); H04W 16/14 (2013.01)] | 6 Claims |
1. A method of performing device to device, D2D, communication between a first user equipment device and a second user equipment device using transmission resources being used for transmissions to a cellular network entity by a third user equipment device, the method comprising performing a demodulation scheme for demodulating transmissions by the third user equipment device in order to perform interference cancellation to cancel signals received from the third user equipment device prior to demodulating signals received from the second user equipment device;
wherein the demodulation scheme comprises evaluating demodulation reference signals transmitted by the third user equipment device;
wherein a modulation scheme used by the third user equipment device is determined by:
measuring a signal power of reference symbols of the reference signals for a plurality of sub-carriers;
selecting a predetermined number of sub-carriers having a reference signal power above a threshold;
applying an assumed demodulation scheme to the signals in these selected sub-carriers;
determining whether an error power is below a threshold in which case a further assumed demodulation scheme is applied until an error power is below the threshold.
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