The compression of wireless base station lte-ir data using adaptive frequency domain floating-point coding

The transmission rate of uplink and downlink has been increasing with the application of Long Term Evolution (LTE). Correspondingly, for LTE wireless distributed base station, the amount of data transferred between Base Band Unit and Radio Remote Units has been growing. But nowadays, the used equipment can only support a limited interface rate. Aiming at this problem, this paper proposes an adaptive frequency domain floating-point coding (AFFC) for the data of optical fiber interface-in-phase and quadrature data (IQ data). In our method, IQ data is firstly converted into frequency domain by fast Fourier Transformation, and we can find its block sparse distribution; secondly, we use the block floating-point coding to compress IQ data, and use Hoffman code to compress block index. Simulation results show the AFFC can compress the IQ data bits effectively and achieve the purpose of decreasing bandwidth of LTE-Ir interface. Compared with the existing compression algorithms in time domain, the proposed algorithm could achieve higher compression rate, and smaller magnitude of the error vector.