Abstract: A transmitter for transmitting payload data and emergency information using data symbols in a single-carrier or multi-carrier broadcast system comprises a modulator configured to modulate one or more transmission symbols with signaling data for use in detecting and recovering the payload data at a receiver and to modulate one or more transmission symbols with the payload data. An emergency information receiver receives emergency information carrying information of an actual emergency. An emergency information embedder embeds emergency information into one or more transmission symbols, wherein the emergency information is embedded within a predetermined time period after its reception by using a resource used for carrying signaling data and/or payload data if no emergency information shall be transmitted. A transmission unit transmits the transmission symbols.

Abstract: A transmitter for transmitting payload data and emergency information using data symbols in a single-carrier or multi-carrier broadcast system comprises a modulator configured to modulate one or more transmission symbols with signaling data for use in detecting and recovering the payload data at a receiver and to modulate one or more transmission symbols with the payload data. An emergency information receiver receives emergency information carrying information of an actual emergency. An emergency information embedder embeds emergency information into one or more transmission symbols, wherein the emergency information is embedded within a predetermined time period after its reception by using a resource used for carrying signaling data and/or payload data if no emergency information shall be transmitted. A transmission unit transmits the transmission symbols.

Abstract: A transmitter transmits payload data using Orthogonal Frequency Division Multiplexed (OFDM) symbols. The first OFDM symbol is a first type having a number of sub-carriers which is less than or equal to the number of sub-carriers of the one or more second OFDM symbols of a second type and a guard interval for the first OFDM symbol is selected in dependence upon the longest possible guard interval of the second OFDM symbol. Accordingly an OFDM communications system can be formed in which data is transmitted using a frame structure in which a guard interval is adapted to allow a mix of different types of OFDM symbols.

Abstract: A transmitter for transmitting payload data and emergency information using data symbols in a single-carrier or multi-carrier broadcast system includes a modulator configured to modulate one or more transmission symbols with signaling data for use in detecting and recovering the payload data at a receiver and to modulate one or more transmission symbols with the payload data. An emergency information receiver receives emergency information carrying information of an actual emergency. An emergency information embedder embeds emergency information into one or more transmission symbols, wherein the emergency information is embedded within a predetermined time period after its reception by using a resource used for carrying signaling data and/or payload data if no emergency information shall be transmitted. A transmission unit transmits the transmission symbols.

Abstract: A transmitter transmits payload data using Orthogonal Frequency Division Multiplexed (OFDM) symbols. The first OFDM symbol is a first type having a number of sub-carriers which is less than or equal to the number of sub-carriers of the one or more second OFDM symbols of a second type and a guard interval for the first OFDM symbol is selected in dependence upon the longest possible guard interval of the second OFDM symbol. Accordingly an OFDM communications system can be formed in which data is transmitted using a frame structure in which a guard interval is adapted to allow a mix of different types of OFDM symbols.

Abstract: A transmitter transmits payload data using Orthogonal Frequency Division Multiplexed (OFDM) symbols. The first OFDM symbol is a first type having a number of sub-carriers which is less than or equal to the number of sub-carriers of the one or more second OFDM symbols of a second type and a guard interval for the first OFDM symbol is selected in dependence upon the longest possible guard interval of the second OFDM symbol. Accordingly an OFDM communications system can be formed in which data is transmitted using a frame structure in which a guard interval is adapted to allow a mix of different types of OFDM symbols.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: A receiver receiving data includes: a first receiver configured to receive data in a first frequency band; a second receiver configured to receive second data in a second frequency band, the second frequency band being a subset of the first frequency band; and a data selector configured to select the frequency of operation of the second receiver from within the second frequency band in accordance with information representing the physical geographical location of the receiving device.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: A transmitter transmits payload data using Orthogonal Frequency Division Multiplexed (OFDM) symbols. The first OFDM symbol is a first type having a number of sub-carriers which is less than or equal to the number of sub-carriers of the one or more second OFDM symbols of a second type and a guard interval for the first OFDM symbol is selected in dependence upon the longest possible guard interval of the second OFDM symbol. Accordingly an OFDM communications system can be formed in which data is transmitted using a frame structure in which a guard interval is adapted to allow a mix of different types of OFDM symbols.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: A transmitter transmits data to a receiver using OFDM symbols including plural sub-carrier symbols, some carrying data symbols and some carrying pilot symbols. A data formatter can form the data for transmission into sets of data symbols for each OFDM symbol, and an OFDM symbol builder can receive each set of data symbols from the data formatter and combine the data symbols with pilot symbols. A modulator can map the data symbols and the pilot symbols onto modulation symbols and modulate the plural sub-carriers to form the OFDM symbols. An inverse Fourier transform can convert the OFDM symbols from the frequency domain to the time domain, and a guard interval inserter can add a guard interval to each of the OFDM symbols by copying a part of the OFDM symbols and appending the copied part sequentially in the time domain to the OFDM symbols.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: A transmitter for transmitting payload data and emergency information using data symbols in a single-carrier or multi-carrier broadcast system includes a modulator configured to modulate one or more transmission symbols with signaling data for use in detecting and recovering the payload data at a receiver and to modulate one or more transmission symbols with the payload data. An emergency information receiver receives emergency information carrying information of an actual emergency. An emergency information embedder embeds emergency information into one or more transmission symbols, wherein the emergency information is embedded within a predetermined time period after its reception by using a resource used for carrying signaling data and/or payload data if no emergency information shall be transmitted. A transmission unit transmits the transmission symbols.

Abstract: A transmitter transmits data to a receiver using OFDM symbols including plural sub-carrier symbols, some carrying data symbols and some carrying pilot symbols. A data formatter can form the data for transmission into sets of data symbols for each OFDM symbol, and an OFDM symbol builder can receive each set of data symbols from the data formatter and combine the data symbols with pilot symbols. A modulator can map the data symbols and the pilot symbols onto modulation symbols and modulate the plural sub-carriers to form the OFDM symbols. An inverse Fourier transform can convert the OFDM symbols from the frequency domain to the time domain, and a guard interval inserter can add a guard interval to each of the OFDM symbols by copying a part of the OFDM symbols and appending the copied part sequentially in the time domain to the OFDM symbols.

Abstract: A receiver receiving data includes: a first receiver configured to receive data in a first frequency band; a second receiver configured to receive second data in a second frequency band, the second frequency band being a subset of the first frequency band; and a data selector configured to select the frequency of operation of the second receiver from within the second frequency band in accordance with information representing the physical geographical location of the receiving device.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: The receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the continuous pilot symbol pattern. The continuous pilot symbols are present at the same sub-carrier locations in first OFDM symbols and as second OFDM symbols. A transmitter is also provided.

Abstract: A receiver comprises a demodulator configured to detect a signal representing the OFDM symbols and to generate a sampled digital version of the OFDM symbols in the time domain. A Fourier transform processor is configured to receive the time domain digital version of the OFDM symbols and to form a frequency domain version of the OFDM symbols, from which the pilot symbol bearing sub-carriers and the data symbol bearing sub-carriers can be recovered. A detector is configured to recover the data symbols from the data bearing sub-carriers of the OFDM symbols and to recover the pilot symbols from the pilot bearing sub-carriers of the OFDM symbols in accordance with the scattered pilot symbol pattern and the continuous pilot symbol pattern. The scattered pilot symbol pattern is one of a plurality of scattered pilot symbol patterns and the continuous pilot pattern is independent of the scattered pilot symbol pattern.