Sounding reference signal processing for LTE

摘要

A wireless communication receiver including a serial to parallel converter receiving an radio frequency signal, a fast Fourier transform device connected to said serial to parallel converter converting NFFT corresponding serial signals into a frequency domain; an EZC root sequence unit generating a set of root sequence signals; an element-by-element multiply unit forming a set of products including a product of each of said frequency domain signals from said fast Fourier transform device and a corresponding root sequence signal, an NSRS-length IDFT unit performing a group cyclic-shift de-multiplexing of the products and a discrete Fourier transform unit converting connected cyclic shift de-multiplexing signals back to frequency-domain.

主权项

1. A wireless communication receiver comprising:
a serial-to-parallel converter receiving a time sample sequence and generating parallel signals; a fast Fourier transform (FFT) device connected to said serial-to-parallel converter and converting said signals from a time domain into a frequency domain; an Extended Zadoff-Chu (EZC) root sequence unit generating a set of root sequence signals; an element-by-element multiply unit connected to said FFT device and said EZC root sequence unit, said element-by-element multiply unit forming a set of products Y including a product of each of said frequency domain signals from said FFT device and a complex conjugate of one of said corresponding root sequence signals X; an Inverse Discrete Fourier Transform (IDFT) unit connected to said element-by-element multiply unit performing a group cyclic-shift de-multiplexing of said products to compute an impulse response for each multiplexed channel, wherein said group cyclic shift de-multiplexing performed by said IDFT unit includes:
Y=FNSRSNFFT(r)y=FNSRS−1diag(X*YT) where: Y is the frequency domain product of an element-wise multiplication, r is the received time sample sequence, y is the time domain product of an element-wise multiplication, FNSRSNFFT is a NSRS by NFFT matrix corresponding to NFFT-point FFT and NSRS sub-carriers de-mapping, X is the expected root sequence; and FNSRS is a NSRS by NSRS matrix, thereby producing for each Sounding Reference Signal (SRS) comb a concatenated Channel Impulse Response (CIR) sequence y of all received wireless users multiplexed on a same root sequence; and a discrete Fourier transform unit connected to said IDFT unit to convert said impulse responses back to frequency domain.