A transmit filter for a stream of OFDM symbols has a remapper, Infinite Impulse Response (IIR) filter and a controller, the transmit filter operating on a stream of OFDM symbols. The transmit filter accepts symbols to be transmitted, the re-mapper re-orders them, the IIR filters the re-ordered stream, and a controller provides an output by rearranging the filtered symbols. The incoming symbol stream contains a series of symbols, each followed by a guard interval, where each guard interval has a first Tg symbol interval, and a second Tg symbol interval, the remapper generating a re-ordered stream having a first Tg symbol interval, a second Tg symbol interval and the symbol, the output of the IIR filter thereby generating a filtered first Tg symbol, a filtered second Tg symbol, and a filtered symbol, and the controller forms the transmit output by discarding the filtered first Tg symbol and outputting, in sequence, the filtered second Tg symbol, the filtered symbol, and a copy of the filtered second Tg symbol. The filtered second Tg symbol may be saved into a local buffer at the time it is initially output for use following the current symbol.