Patent ID: 9118410
Filing Date: 2015-08-25
Classification: H04B,H04W

Abstract:
1. A method of providing parameters as feedback to two terminals according to channel conditions by a relay for two-way communication in a two-way relaying system using PNC (physical network coding), the method comprising: (a) quantizing phase difference information of two-way channels of the two terminals in consideration of whether or not a ratio of a minimum distance between constellation points is periodic according to modulation level; and (b) transmitting feedback information as a limited number of bits to the two terminals, the feedback information containing at least one of the phase difference information and the power control information of the two terminals, wherein a number of bits for the phase difference information or a number of bits for the power control information is determined according to the modulation level, and wherein, if the modulation level is QPSK (quadrature phase shift keying), said step (a) comprises: reducing the number of bits for the phase difference information by one bit and generating codebook candidates within a range of [0, π] in consideration of a period for the ratio of the minimum distance being π, and determining the phase difference information to be a codebook candidate satisfying a particular criterion from among the codebook candidates.