DVB-C2 generation and reception

Abstract

The present invention relates to DVB-C2 generation apparatus and methods for generating transmission signals (s (t) ) from DVB-C2 symbols, each comprising a plurality of subcarriers, for transmission in a multi-carrier data transmission system. In DVB-C2 systems using the concept of Absolute DVB-C2 common phase rotations of the subcarriers of said symbol with respect to adjacent symbols of said DVB-C2 transmission signal generally appear when mixing to a higher frequencies baseband signal. To avoid those common phase rotations, according to a embodiment of the proposed apparatus and method a selected mixing frequency is used for mixing said complex time-domain samples of said symbols from a baseband frequency up to a passband frequency by use of a mixing frequency (fc) to obtain said DVB - C2 transmission signal (s (t) ), wherein the mixing frequency (fc) is selected such that common phase rotations of the subcarriers of said symbols with respect to adjacent symbols of said transmission signal ( (s (t) ) ) are avoided or compensation after said mixing. Further embodiments for compensation of such common phase rotations are provided, in which means are adapted to rotate the baseband symbols such that the passband frequency signal is complying with the DVB-C2 standard. The present invention relates to OFDM generation apparatus and methods for generating OFDM transmission signals (s(t)) from OFDM symbols, each comprising a plurality of OFDM subcarriers, for transmission in a multi-carrier data transmission system. In OFDM systems using the concept of Absolute OFDM and / or using Segmented OFDM common phase rotations of the OFDM subcarriers of said OFDM symbol with respect to adjacent OFDM symbols of said OFDM transmission signal generally appear. To avoid or compensate those common phase rotations, according to a embodiment of the proposed apparatus and method a selected mixing frequency is used for mixing said complex time-domain samples of said OFDM symbol from a baseband frequency up to a passband frequency by use of a mixing frequency (fc) to obtain said OFDM transmission signal (s(t)), wherein the mixing frequency (fc) is selected such that common phase rotations of the OFDM subcarriers of said OFDM symbol with respect to adjacent OFDM symbols of said OFDM transmission signal ((s (t))) are avoided or compensated after said mixing. Further embodiments for avoidance or compensation of such common phase rotations are provided.

Description

technical field [0001] The present invention relates to an OFDM generation device and method for generating an OFDM transmission signal from OFDM symbols for transmission in a multi-carrier data transmission system, wherein each OFDM symbol comprises a plurality of OFDM subcarriers. [0002] The invention also relates to a transmission device and method, a corresponding receiving device and method, a data transmission system and a computer program for implementing the OFDM generation method on a computer. [0003] The present invention relates in particular to the field of broadcasting, in particular to the field of Digital Video Broadcasting (DVB), and in particular to devices, systems and methods according to the DVB-C2 standard or the forthcoming DVB-NGH standard. Background technique [0004] According to the DVB-C2 standard described in the DVB-C2 technical specification (DVB blue book A138 "Digital Video Broadcasting (DVB); Frame structure channel coding and modulation...

AI Technical Summary

Problems solved by technology

However, this means that during OFDM generation with an RF carrier frequency, the baseband signal will not be able to be shifted to any RF carrier frequency (hereinafter also referred to as "mixing frequency")

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