Transmitter and receiver and methods of transmitting and receiving

Abstract

A receiver for detecting and recovering payload data from a received signal comprises a radio frequency demodulation circuit, a detector circuit and a demodulator circuit. The radio frequency demodulation circuit detects the received signal. The received signal carries the payload data as OFDM symbols in one or more of a plurality of time divided frames, each frame including a bootstrap signal, a preamble signal and a plurality of sub-frames. The demodulator circuit detects bootstrap OFDM symbols to identify communications parameters for detecting the fixed length signalling data, detects the fixed length signalling data to identify the communications parameters for detecting the variable length signalling data, detects the variable length signalling data, and uses the fixed and variable length signalling data to detect the payload data.

1 . A receiver comprising:
 radio frequency demodulation circuitry configured to detect a received signal comprising Orthogonal Frequency Division Multiplexed (OFDM) symbols in one or more of a plurality of time divided frames, each frame including a bootstrap signal, a preamble signal and a plurality of subframes each of which carry payload data modulated on a plurality of second OFDM symbols, the preamble signal comprising one or more OFDM symbols modulated with signalling data, the Fast Fourier Transform (FFT) size of the one or more OFDM symbols of the preamble signal being the same FFT size as for the second OFDM symbols of first of the plurality of subframes; and   demodulator circuitry configured to detect the signalling data from the OFDM symbols of the preamble signal and to use the signalling data to detect the payload data modulated on the second OFDM symbols of the first of the subframes.