Abstract: There is being disclosed an OFDM signal receiver for detecting carrier frequency offset. When FFT transform of the signal is processed in the receiver, an estimator applies the spectrum shape of the FFT transform for estimating the carrier frequency offset.

Abstract: An input bit stream is phase rotated by reversing bit pairs and inverting bits. The manipulated bit stream is mapped to a symbol and the mapped symbol is converted to the time domain such that an output of the time domain conversion is an ordered set of N samples that allow efficient cyclic prefix insertion without rotation at the symbol level. A first portion of the set of samples is stored in a buffer, and the complete set of samples is output followed by the buffered first portion of the set of samples for transmission. The set of samples can be NIFFT samples of an OFDM symbol and the first portion can be NCP samples that make up the cyclic prefix CP. Re-ordering the bits can be done by swapping bit pairs and inverting one of the swapped pairs, or by trivial (1, ?1, ?j) phase rotation. The buffer is ¼ the length of prior art OFDM buffers and CP-related processing delays are significantly reduced.

Abstract: The present invention relates to a method and apparatus for implementing a discrete Fourier transformation (DFT) of a predetermined vector size, wherein at least one enhanced DFT module is provided by using at least one type of DFT module including multiplication by first and second types of twiddle factors in respective different multiplication stages separated by an intermediate integration stage, and generating the enhanced DFT module by combining the at least one type of DFT module with a recursive stage configured to multiply by a third type of twiddle factor and to selectively switch between a bypass function and a butterfly function in said recursive stage. Thereby, an implementation of non 2x-radix Fourier transformation can be achieved with moderate hardware complexity.

Abstract: Mobile handheld terminals receiving DVB transmission require relatively low power consumption and TDM based transmission can be used to reduce power of the terminals. In order find pilot carrier position at least two symbols are accessed which are adapted to establish a correspondence pattern for pilot carriers in a matrix of the at least two symbols. Carriers of the first symbol are correlated with the corresponding carriers of the second symbol within the matrix for determining a correlation maximum for indicating a pilot carrier position.

Abstract: An apparatus for generating filtered and downsampled data comprises a calculation unit, a polyphase addition unit and a downsampling unit operable in a data decimation phase and a data preserving phase. The calculation unit is arranged to receive input data and is configured to generate a first data part during the data decimation phase and a second part during the data preserving phase. The polyphase addition unit is configured to generate a third data part in dependence on said first and second data parts and to output said third data part to the downsampling unit.

Abstract: An input bit stream is phase rotated by reversing bit pairs and inverting bits. The manipulated bit stream is mapped to a symbol and the mapped symbol is converted to the time domain such that an output of the time domain conversion is an ordered set of N samples that allow efficient cyclic prefix insertion without rotation at the symbol level. A first portion of the set of samples is stored in a buffer, and the complete set of samples is output followed by the buffered first portion of the set of samples for transmission. The set of samples can be NIFFT samples of an OFDM symbol and the first portion can be NCP samples that make up the cyclic prefix CP. Re-ordering the bits can be done by swapping bit pairs and inverting one of the swapped pairs, or by trivial (1, ?1, ?j) phase rotation. The buffer is ¼ the length of prior art OFDM buffers and CP-related processing delays are significantly reduced.

Abstract: There is being disclosed an OFDM signal receiver for detecting carrier frequency offset. When FFT transform of the signal is processed in the receiver, an estimator applies the spectrum shape of the FFT transform for estimating the carrier frequency offset.

Abstract: The present invention proposes a signal processor for Fast Fourier Transformation, FFT, of MR, MR>1, input data streams of 2k samples each, supplied in parallel. After multiplexing the input data streams in an interlaced manner, the resulting stream is subjected to FFT. The FFT device has a pipeline architecture composed of k stages with a respective feedback path including a single delay element per each stage of the pipeline architecture. The delay element and timing signals are adapted to cope with FFT processing of the multiplexed streams using the single FFT device only. After processing, the FFT processed data stream is demultiplexed. The present invention also concerns a corresponding signal processing method.

Abstract: The present invention proposes a signal processor for Fast Fourier Transformation, FFT, of MR, MR>1, input data streams of 2k samples each, supplied in parallel. After multiplexing the input data streams in an interlaced manner, the resulting stream is subjected to FFT. The FFT device has a pipeline architecture composed of k stages with a respective feedback path including a single delay element per each stage of the pipeline architecture. The delay element and timing signals are adapted to cope with FFT processing of the multiplexed streams using the single FFT device only. After processing, the FFT processed data stream is demultiplexed. The present invention also concerns a corresponding signal processing method.

Abstract: The present invention relates to a method and apparatus for implementing a discrete Fourier transformation (DFT) of a predetermined vector size, wherein at least one enhanced DFT module is provided by using at least one type of DFT module including multiplication by first and second types of twiddle factors in respective different multiplication stages separated by an intermediate integration stage, and generating the enhanced DFT module by combining the at least one type of DFT module with a recursive stage configured to multiply by a third type of twiddle factor and to selectively switch between a bypass function and a butterfly function in said recursive stage. Thereby, an implementation of non 2x-radix Fourier transformation can be achieved with moderate hardware complexity.

Abstract: In telecommunication systems, in particular OFDM telecommunication systems, there is a Fourier transformer for transforming the data signal from time to frequency domain. The present invention proposes to define the bit-reversed output of the Fourier transformer at least as a part of a deinterleaving process in a receiver. In a transmitter, the bit-reversed input of the inverse Fourier transformer is used accordingly.

Abstract: The present invention relates to a method and apparatus for implementing a discrete Fourier transformation (DFT) of a predetermined vector size, wherein at least one DFT module is configured to perform DFTs of a first predetermined number and of a vector size corresponding to a second predetermined number, to multiply by twiddle factors, and to perform DFTs of said second predetermined number and of a vector size corresponding to said first predetermined number. At least two of the at least one DFT module are combined to obtain the predetermined vector size. Thereby, an implementation of non 2x-radix Fourier transformation can be achieved with moderate hardware complexity.

Abstract: Mobile handheld terminals receiving DVB transmission require relatively low power consumption and TDM based transmission can be used to reduce power of the terminals. In order find pilot carrier position at least two symbols are accessed which are adapted to establish a correspondence pattern for pilot carriers in a matrix of the at least two symbols. Carriers of the first symbol are correlated with the corresponding carriers of the second symbol within the matrix for determining a correlation maximum for indicating a pilot carrier position.

Abstract: Mobile handheld terminals receiving DVB transmission require relatively low power consumption and TDM based transmission can be used to reduce power of the terminals. In order find pilot carrier position at least one symbol is accessed which is adapted to establish a correspondence pattern for pilot carriers in a matrix of the symbols. Carriers of the symbol are power accumulation summed within the matrix for determining a power accumulation sum maximum for indicating a pilot carrier position.

Abstract: The invention relates to an analog quadrature demodulator (100), which comprises analog domain means for splitting an incoming signal into an in-phase (I) branch signal and a quadrature (Q) branch signal and an analog domain correction circuitry (106, 107) for controllably causing the in-phase (I) branch signal and the quadrature (Q) branch signal to co-operate with each other via the correction circuitry (106, 107) so as to correct the quadrature error.