Analysis and Mitigation of Interference to the LTE Physical Control Format Indicator Channel

Abstract

In LTE, the Physical Control Format Indicator Channel (PCFICH) is a downlink control channel that indicates the number of OFDM symbols used by the primary downlink control channel in each sub frame. Even though the PCFICH only carries two bits of control information, it is essential to the operation of LTE. Since the PCFICH is a vital physical channel that only occupies a small fraction of the downlink signal, it acts as a weak link in terms of vulnerability to targeted interference. Due to recent interest in using LTE for military and public safety applications, it would be beneficial to better understand this vulnerability. This paper investigates the performance of the PCFICH under various harsh wireless conditions and proposes strategies to prevent interference against the PCFICH from causing link degradation.