Patent ID: 8817898
Filing Date: 2014-08-26
Classification: H04L

Abstract:
1. A method for filtering a received Orthogonal Frequency Division Multiplexed (OFDM) signal to reduce noise, the OFDM signal comprising a plurality of symbols n in the time direction, each symbol comprising a plurality of sub-carriers k in the frequency direction, each a-th sub-carrier of each symbol being transmitted as a pilot sub-carrier with known amplitude and phase, and each symbol having its pilot sub-carriers spaced by b sub-carriers relative to the adjacent symbol, the method comprising: producing a filtered version of a selected pilot sub-carrier to be used in subsequent interpolation, by inputting into respective taps of an m-tap filter, m pilot sub-carriers which each have different positions in the time direction and in the frequency direction and such that each position satisfies a relationship between n and k so that the m pilot sub-carriers collectively define a single linear diagonal line in the time frequency plane.