Abstract:
A receiver for receiving data in a broadcast system includes a broadcast receiver that receives via the broadcast system a receiver input data stream including plural channel symbols represented by constellation points in a constellation diagram, a demodulator that demodulates the channel symbols into codewords, and a decoder that decodes the codewords into output data words. A redundancy calculator determines a required amount of redundancy data required for correct demodulation and decoding by use of the originally received channel symbol and additional redundancy data. A broadband request unit requests, if demodulation of a channel symbol and/or decoding of a codeword is erroneous or likely to fail, a required amount of redundancy data via a broadband system, that is received by a broadband receiver via said broadband system. The demodulator and/or the decoder is configured to use the redundancy data for demodulation and decoding, respectively.
Abstract:
A control device for use in a broadcast system includes a broadcast controller that controls a broadcast transmitter of the broadcast system that broadcasts broadcast signals in a coverage area for reception by terminals including a broadcast receiver and a broadband receiver, and a broadband controller that controls a broadband server of a broadband system that provides redundancy data to terminals within the coverage area. The broadband controller is configured to control the provision of redundancy data by the broadband server for use by one or more terminals which use the redundancy data together with broadcast signals received via said broadcast system for recovering content received within the broadcast signals and/or provided via the broadband system.
Abstract:
A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groups of constellations each comprising one or more constellations.
Abstract:
A coding and modulation apparatus and method are presented. The apparatus (10) comprises an encoder (11) that encodes input data into cell words, and a modulator (12) that modulates said cell words into constellation values of a non-uniform constellation. The modulator (12) is configured to use, based on the total number M of constellation points of the constellation, the signal-to-noise ratio SNR in dB and the channel characteristics, a non-uniform constellation from a group of constellations comprising one or more of predetermined constellations defined by the constellation position vector u1 . . . v, wherein v=sqrt(M)/2−1.
Abstract:
LDPC coding is executed using a check matrix of an LDPC code whose code length is 736 bits and whose code rate is 1/4, and modulation is executed using a repetition unit that has an LDPC code obtained by the LDPC coding, repeatedly arranged therein. The LDPC code includes information bits and parity bits, the check matrix includes an information matrix portion corresponding to the information bits and a parity matrix portion corresponding to the parity bits, the parity matrix portion has a stepwise structure, the information matrix portion is indicated by a check matrix initial value table, and the check matrix initial value table is a predetermined table indicating positions of elements of “1” of the information matrix portion for each eight columns. This technique is applicable to, for example, information transmission using the LDPC code.
Abstract:
A control device for use in a broadcast system includes a broadcast controller that controls a broadcast transmitter of the broadcast system that broadcasts signals in a coverage area for reception by terminals including a broadcast receiver and a broadband receiver, and a broadband controller that controls a broadband server of a broadband system that provides redundancy data to terminals within the coverage area. The broadband controller is configured to control the provision of redundancy data by the broadband server for use by one or more terminals which use the redundancy data together with broadcast signals received via said broadcast system for recovering content received within the broadcast signals and/or provided via the broadband system.
Abstract:
An apparatus and a corresponding method for mapping payload data of mapping input data streams onto a mapping output data stream having a channel bandwidth for transmission in a multi-carrier broadcast system includes first and second frame forming mechanisms. The first frame forming mechanism is adapted to form first frames having a first frame structure and the second frame forming mechanism is adapted to form second frames having a second frame structure. Preferably, in a second frame structure the data blocks of a particular mapping input data stream are spread in time and frequency over various data symbols and various data segments of the second frames to provide high robustness against disturbances. The payload portion of the second frame is preferably segmented into various data segments enabling use of a narrow-band receiver, even if both the first and second frames cover the same total channel bandwidth.
Abstract:
A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groups of constellations each comprising one or more constellations.
Abstract:
A coding and modulation apparatus and method are presented, particularly for use in a system according to IEEE 802.11. The apparatus comprises an encoder configured to encode input data into cell words according to a binary convolutional code, BCC, or a low density parity check code, LDPC, and a modulator configured to modulate said cell words into constellation values of a non-uniform constellation and to assign bit combinations to constellation values of the used non-uniform constellation, wherein said modulator is configured to use, based on the code used by the encoder, the total number M of constellation points of the constellation and the code rate.
Abstract:
A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groups of constellations each comprising one or more constellations.