Compression and de-compression of complex valued OFDM data for a radio base station

摘要

A compression method is disclosed, which comprises receiving an OFDM data block comprising a plurality of complex valued data samples wherein each in-phase and quadrature sample value is represented by a first number of bits. The method also comprises calculating an average of absolute sample values of the OFDM data block and mapping the average absolute sample value to a standard deviation value. The method further comprises quantizing each of the sample values using quantization thresholds scaled by the standard deviation value to produce quantized in phase and quadrature sample value representations, each comprising a second number of bits, and mapping the standard deviation value and the quantized sample value representations to an OFDM transmission frame. Corresponding de-compression method, compressor, de-compressor and network node are also disclosed.

主权项

1. A compression method comprising:
receiving a time-domain complex-valued Orthogonal Frequency-Division Multiplex (OFDM) data block comprising a plurality of complex-valued data samples wherein each complex-valued data sample comprises an in-phase sample value and a quadrature sample value, each represented by a first number, M, of bits; determining an absolute sample value of each of the in-phase sample value and the quadrature sample value for each of the complex-valued data samples; calculating an average of the absolute sample values of the time domain complex-valued OFDM data block to produce an average absolute sample value; mapping the average absolute sample value to a standard deviation value associated with the absolute sample values based on a mapping function which expresses the average absolute sample value as a first function minus a second function, wherein the first function is a function of the first number of bits and the second function is a sum of 2(M-1)−1 terms, each term comprising a function of the standard deviation; for each of the complex-valued data samples, quantizing each of the in-phase sample value and the quadrature sample value using a number of quantization thresholds scaled by the standard deviation value to produce quantized in-phase and quadrature sample value representations, each comprising a second number of bits, wherein the second number of bits are fewer than the first number of bits; and mapping the standard deviation value and the quantized in-phase and quadrature sample value representations to an OFDM transmission frame.