Experiments on Frequency Error Compensation Using Synchronization Channel in OFDM Radio Access

Hidekazu TAOKA  Fumiaki ITO  Keiji TAKAKUSAKI  Mamoru SAWAHASHI 

Publication
IEICE TRANSACTIONS on Communications  Vol.E92-B  No.5  pp.1619-1626
Publication Date: 2009/05/01
Online ISSN: 1745-1345
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Section on Radio Access Techniques for 3G Evolution)
Category: 
Keyword: 
OFDM,  AFC,  SCH,  downlink,  Evolved UTRA, 

Full Text: PDF(2.3MB)

Summary: 
This paper experimentally investigates the effect of frequency error compensation provided by demodulation automatic frequency control (AFC) using the Synchronization Channel (SCH) in downlink OFDM radio access. The implemented OFDM receiver compensates for the frequency error caused by the difference in frequency between a base station (BS) and a user equipment (UE) using a time-division multiplexed SCH signal and that caused by the Doppler shift generated by the mobility of a user using reference signals with staggered multiplexing. Experimental results show that even when the standard oscillator frequency of the UE cannot be made to track the more accurate frequency of a BS, demodulation AFC can suppress the residual frequency error to a sufficiently low level, i.e., within 0.3 ppm, using the SCH so that the degradation in the block error rate of the physical broadcast channel control signals is slight, i.e., within approximately 0.1 dB, with respect to the case without frequency error for speeds greater than 350 km/h.