Abstract: An Orthogonal Frequency Division Multiplexing, OFDM, transmitter comprises a signalling data generator (113) which generates a set of data symbols indicative of physical layer characteristics of data transmissions from the OFDM transmitter (100). A first symbol generator (115) and second symbol generator (117) generates a first and second OFDM signalling symbol by allocating the set of data symbols to subcarriers. The allocation of the physical layer data symbols to subcarriers is different for the first OFDM signalling symbol and the second OFDM signalling symbol. A data packet generator (105) and transmitter (101) generate a data packet and transmit this to an OFDM receiver (300). The OFDM receiver (300) determines the physical layer data symbols by combining the data symbols of corresponding subcarriers of the first and second OFDM signalling symbols and uses the resulting information to decode the user data of the data packet.

Abstract: Multiple Transmit Multiple Receive Orthogonal Frequency Division Multiplexing (‘OFDM’) comprising generating bit streams and corresponding sets of N frequency domain carrier amplitudes ({tilde over (s)}(kN+j), 0?j?N?1) modulated as OFDM symbols subsequently to be transmitted from a transmitter, where k is the OFDM symbol number and j indicates the corresponding OFDM carrier number. Affix information is inserted at the transmitter into guard intervals between consecutive time domain OFDM symbols and are used at the receiver to estimate the Channel Impulse Response (Hlm) of the transmission channels, the estimated Channel Impulse Response (?lm) being used to demodulate the bit streams in the signals received at the receiver.

Abstract: An Orthogonal Frequency Division Multiplexing, OFDM, transmitter comprises a signalling data generator (113) which generates a set of data symbols indicative of physical layer characteristics of data transmissions from the OFDM transmitter (100). A first symbol generator (115) and second symbol generator (117) generates a first and second OFDM signalling symbol by allocating the set of data symbols to subcarriers. The allocation of the physical layer data symbols to subcarriers is different for the first OFDM signalling symbol and the second OFDM signalling symbol. A data packet generator (105) and transmitter (101) generate a data packet and transmit this to an OFDM receiver (300). The OFDM receiver (300) determines the physical layer data symbols by combining the data symbols of corresponding subcarriers of the first and second OFDM signalling symbols and uses the resulting information to decode the user data of the data packet.

Abstract: Multiple Transmit Multiple Receive Orthogonal Frequency Division Multiplexing (‘OFDM’) comprising generating bit streams and corresponding sets of N frequency domain carrier amplitudes ({tilde over (s)}(kN+j), 0?j?N?1) modulated as OFDM symbols subsequently to be transmitted from a transmitter, where k is the OFDM symbol number and j indicates the corresponding OFDM carrier number. Affix information is inserted at the transmitter into guard intervals between consecutive time domain OFDM symbols and are used at the receiver to estimate the Channel Impulse Response (Hlm) of the transmission channels, the estimated Channel Impulse Response (?lm) being used to demodulate the bit streams in the signals received at the receiver.