Title :
A Low-Complexity Sequential Encoder for Threshold Vector Perturbation
Author :
Masouros, Christos ; Sellathurai, Mathini ; Ratnarajah, Tharm
Author_Institution :
Dept. of Electr. & Electron. Eng., Univ. Coll. London, London, UK
Abstract :
We propose a sequential encoder for threshold vector perturbation (TVP) precoding in the downlink of K-user multiple input single output (MISO) systems, that introduces complexity savings in the encoding of the data symbols at the base station (BS) transmitter. As opposed to conventional TVP where a thresholded K-dimensional search is carried out to obtain the perturbation vectors that satisfy given signal to noise ratio (SNR) thresholds at the receiver, here we explore a sequential approach that involves the encoding of a subset of transmit symbols L<;K to obtain the required vectors. This limits the dimensionality of the associated sphere search, while still obtaining SNR-guaranteeing perturbation vectors. The presented analysis and results show significant complexity savings with the proposed scheme compared to conventional TVP and VP schemes.
Keywords :
codecs; perturbation techniques; precoding; radio receivers; (SNR) thresholds; K-user multiple input single output; MISO systems; SNR-guaranteeing perturbation vectors; TVP; TVP precoding; VP schemes; base station transmitter; complexity savings; data symbols; encoding; low-complexity sequential encoder; perturbation vectors; signal to noise ratio; sphere search; threshold vector perturbation; thresholded K-dimensional search; transmit symbols; Complexity theory; Downlink; Encoding; Lattices; Optimization; Signal to noise ratio; Vectors; Vector perturbation; complexity reduction; multi-user MISO; sphere encoding;
Journal_Title :
Communications Letters, IEEE
DOI :
10.1109/LCOMM.2013.101813.131811