FAST DETECTION OF NUMBER OF ANTENNA PORTS IN LTE SYSTEM

Sajal Kumar Das, Om Prakash

Abstract: In LTE system, during initial cell selection UE is unaware about the number of antennas used by eNB for transmission. So, UE blindly tries multiple times to detect the right number of antennas used for transmission in the system. This wastes lot of time and UE processing power, as UE needs to do channel estimation, equalization/demodulation, decoding process multiple times with assumption of 1 or 2 and 4 antenna ports each time. The objective of this paper is to find out a faster and efficient method for detecting the number of antenna ports used by the eNB for signal transmission. A new method is explored for detecting the number of eNB transmit antennas before starting PBCH decoding and CRC checking by exploiting the presence of downlink reference signals at various Resource Element (RE) positions in the Resource Blocks (RB) and using the PBCH SFBC data patterns. This helps for faster detection of number of antennas used for transmission that in turn helps to reduce the UE power consumption as well as reduces the initial cell search time.

Keywords: UE- User Equipment, LTE- Long-Term Evolution, eNB- evolved Node B, RAT- Radio Access Technology, PBCH- Physical Broadcast Channel, SFBC- Space Frequency Block Codes, DL – Down Link.

DOI: https://doi.org/10.15623/ijret.2015.0403027