Title :
Coverage enhancement of PBCH using reduced search Viterbi for MTC in LTE-Advanced networks
Author :
Annamalai, Parthiban ; Das, Sajal Kumar ; Bapat, Jyotsna ; Das, Debabrata
Author_Institution :
Ericsson, Bangalore, India
Abstract :
Machine Type Communication (MTC) is becoming an integral part of the Long Term Evolution - Advanced (LTE-A) cellular network. Challenges arise when some of the MTC devices, due to the nature of their applications, are deployed in low signal locations. As per 3GPP requirements, there is a need for additional coverage enhancement up to 20 dB in comparison with LTE category 1 UE for MTC devices. In the previous works reported till now, Repetition Coding is proposed as an effective technique to achieve the required coverage enhancements at cost of longer decoding time. In low signal conditions where many repetitions are required to build the SNR needed, the decoding delay may be unacceptable. For a LTE-A MTC UE, Physical Broadcast CHannel (PBCH) decoding has a very important role and fast, efficient decoding of PBCH will help to improve the device performance. In this paper, we propose to use well established technique called Reduced Search (RS) Viterbi to improve PBCH decoding performance without compromising the time-to-decode. RS Viterbi technique utilizes a priori knowledge of transmitted bits to reduce the size and complexity of trellis, which in turn also reduces probability of choosing incorrect path, i.e., error. Up to 2.2 dB SNR gain is seen in simulation using the RS Viterbi decoding against the conventional Viterbi decoding, which will contribute in improving the sensitivity of MTC devices for better reachability.
Keywords :
3G mobile communication; Long Term Evolution; Viterbi decoding; broadcast channels; cellular radio; 3GPP requirements; LTE-advanced networks; Long Term Evolution-advanced cellular network; MTC networks; PBCH decoding; RS Viterbi decoding; coverage enhancement; machine type communication; physical broadcast channel decoding; reduced search Viterbi technique; repetition coding; time-to-decode; Computational complexity; Conferences; Decoding; Long Term Evolution; Receivers; Signal to noise ratio; Viterbi algorithm; Coverage Enhancement; LTE; MTC; PBCH; UE;
Conference_Titel :
Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt), 2015 13th International Symposium on
Conference_Location :
Mumbai
DOI :
10.1109/WIOPT.2015.7151061