Abstract: In a digital broadband broadcast transmitter, digital data is time interleaved for transmission, and the time interleaved digital data is transmitted in a digital broadband broadcast transmission towards a plurality of receivers. A cellular transmitter is operated in an apparatus. In the same apparatus, the digital broadband broadcast transmission transmitted by the digital broadband broadcast transmitter is received, and the received digital broadband broadcast transmission is time deinterleaved.

Abstract: The invention is directed to efficient transfer of low bit rate services in a communication system. A synchronization symbol which has known characteristics may be included as a first symbol of digital broadcast frames. The synchronization symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. Low bit rate services are allocated to time slots following the pilot symbol used for synchronization allowing for fast access times with maximum power saving capabilities. A user terminal wakes up just before the synchronization symbol and received the data allocated for the low bit rate services. The user terminal may power off for the remaining time slots which are allocated for higher bit services to conserve power.

Abstract: Embodiments are directed to first and second OFDM pilot symbols. The first and second pilot symbols may have first and second sets, respectively, of allowed, forbidden, and active carrier frequencies. The second sets of carrier frequencies may be formed by frequency shifting the respective first sets by a predetermined frequency, such as the frequency difference between adjacent carriers. An embodiment is directed to frequency translating part of a first received pilot symbol by one carrier interval in a first direction, frequency translating part of a second received pilot symbol by one carrier interval in a second direction that is opposite from the first direction, and forming a correlation by multiplying the frequency translated parts of the first and second pilot symbols by complex conjugates of parts of the pilot symbols upon which frequency translation has not been performed, and summing the multiplication results.

Abstract: Aspects of the invention are directed to service and channel discovery in a digital broadcast network. A pilot synchronization symbol, which has known characteristics, is included as a first symbol of digital broadcast frames. The pilot symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. So, the rest of the signal can be decoded without trial and error methods after the pilot symbol (and any additional synchronization symbols) is decoded. Channels containing digital video broadcast services can be efficiently detected using the known part of the signal. If the fixed known part is not found from the examined signal, then the signal will be considered a non-digital-video-broadcast signal or an empty channel, and the receiver can promptly proceed to a next channel/frequency. In this way, detecting non-digital-video-broadcast and empty channels becomes relatively fast.

Abstract: In a digital broadband broadcast transmitter, digital data is time interleaved for transmission, and the time interleaved digital data is transmitted in a digital broadband broadcast transmission towards a plurality of receivers. A cellular transmitter is operated in an apparatus. In the same apparatus, the digital broadband broadcast transmission transmitted by the digital broadband broadcast transmitter is received, and the received digital broadband broadcast transmission is time deinterleaved.

Abstract: The invention relates to a method for communicating digital data using an orthogonal frequency division multiplexing (OFDM) transmission system (10) including at least one transmitter (600, 601) and receivers (700, 701).

Abstract: In a first aspect, there are received m transmitted signals of a multiple input/multiple output transmission comprising n transmitted signals corresponding to n streams of n different polarizations, where n is a positive integer greater than one, and m is an integer less than n. The m received signals are decoded to obtain information for the corresponding streams. Apparatus and computer programs to implement the invention are also detailed.

Abstract: Embodiments are directed to first and second OFDM pilot symbols. The first and second pilot symbols may have first and second sets, respectively, of allowed, forbidden, and active carrier frequencies. The second sets of carrier frequencies may be formed by frequency shifting the respective first sets by a predetermined frequency, such as the frequency difference between adjacent carriers. An embodiment is directed to frequency translating part of a first received pilot symbol by one carrier interval in a first direction, frequency translating part of a second received pilot symbol by one carrier interval in a second direction that is opposite from the first direction, and forming a correlation by multiplying the frequency translated parts of the first and second pilot symbols by complex conjugates of parts of the pilot symbols upon which frequency translation has not been performed, and summing the multiplication results.

Abstract: Method and system for tolerating impulsive burst noise in pilot based OFDM systems, especially using DVB-T standard. The method contains following steps: 1) recognition of the impulse position and possibly length in the time domain symbol, 2) blanking of those samples of the symbol where significant amount of impulse noise is present, 3) calculating the first estimate of the received signal from the blanked symbol, 4) using a prior information (guard band carriers, pilot carriers) an estimate of the blanked symbol is calculated using inverse FFT on the differences of the observed carrier values from the known values in the frequency domain, 5) correction values for the frequency domain carriers are derived taking the FFT of the restored time domain samples, 6) finally the corrected estimate of the received symbol is derived by summing the correction values of step 5 to the first estimate of carriers derived in step 3.

Abstract: In accordance with at least one embodiment, fixed TDM slot/frame structure and statistical multiplexing are combined. A TDM slot, which is fixed (in size and position) is reserved for a variable bit rate service such that the bit rate of the TDM slot/channel is below the average rate of the service. Such a reserved TDM slot may be referred to as a service specific slot. Since the service specific slot is reserved with a bit rate below the average rate of the service, additional capacity is reserved from a rate matching slot, which may be common for multiple services. In this rate matching slot, the capacity may be shared between services according to any suitable strategy for allotting services to portions of the rate matching slot, including, but not limited to, a statistical multiplexing algorithm.

Abstract: Aspects of the invention are directed to service and channel discovery in a digital broadcast network. A pilot synchronization symbol, which has known characteristics, is included as a first symbol of digital broadcast frames. The pilot symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. So, the rest of the signal can be decoded without trial and error methods after the pilot symbol (and any additional synchronization symbols) is decoded. Channels containing digital video broadcast services can be efficiently detected using the known part of the signal. If the fixed known part is not found from the examined signal, then the signal will be considered a non-digital-video-broadcast signal or an empty channel, and the receiver can promptly proceed to a next channel/frequency. In this way, detecting non-digital-video-broadcast and empty channels becomes relatively fast.

Abstract: The invention is directed to efficient transfer of low bit rate services in a communication system. A synchronization symbol which has known characteristics may be included as a first symbol of digital broadcast frames. The synchronization symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. Low bit rate services are allocated to time slots following the pilot symbol used for synchronization allowing for fast access times with maximum power saving capabilities. A user terminal wakes up just before the synchronization symbol and received the data allocated for the low bit rate services. The user terminal may power off for the remaining time slots which are allocated for higher bit services to conserve power.

Abstract: A receiver 100 for receiving a multi-carrier signal comprises detection means for detecting 801 the presence of impulse interference within the signal and identifying one or more samples of the signal affected by the impulse interference, means for selecting samples to be blanked, means for blanking the selected samples and means 805 for estimating the blanked signal. The selected samples comprise those samples (l0 to l0+k) identified as being affected by impulse interference and at least one of the following: a number of samples x1 preceding the said identified samples (l0 to l0+k) or a number of samples x2 following the said identified samples (l0 to l0+k). The blanking means may define the length of a blanking window 301 to have one of a plurality of different predetermined lengths, using the smallest of the predetermined lengths sufficient to encompass the selected samples.

Abstract: Method and system for reducing impulsive burst noise in less delayed reception in pilot based OFDM systems, especially using DVB-T standard such as Digital Video Broadcasting (DVB) is provided. The method contains following steps: 1) recognition of the impulse position and possibly length in the time domain symbol, 2) blanking of those samples of the symbol where significant amount of impulse noise is present, 3) calculating the first estimate of the received signal from the blanked symbol, 4) deriving correction values for the carrier estimates by applying prior information (pilot carriers), and 5) the corrected estimate of the received symbol is derived by subtracting the correction values of step 4 from the first estimate of carriers derived in step 3. The method and arrangement allow correction of fairly long bursts of impulse noise with minor degradation only. The complexity of the scheme and the additional energy consumption are fairly low.

Abstract: The invention relates to a method for communicating digital data using an orthogonal frequency division multiplexing (OFDM) transmission system (10) including at least one transmitter (600, 601) and receivers (700, 701).

Abstract: Method and system for tolerating impulsive burst noise in pilot based OFDM systems, especially using DVB-T standard. The method contains following steps: 1) recognition of the impulse position and possibly length in the time domain symbol, 2) blanking of those samples of the symbol where significant amount of impulse noise is present, 3) calculating the first estimate of the received signal from the blanked symbol, 4) using a prior information (guard band carriers, pilot carriers) an estimate of the blanked symbol is calculated using inverse FFT on the differences of the observed carrier values from the known values in the frequency domain, 5) correction values for the frequency domain carriers are derived taking the FFT of the restored time domain samples, 6) finally the corrected estimate of the received symbol is derived by summing the correction values of step 5 to the first estimate of carriers derived in step 3.

Abstract: The present invention relates to receivers, and, more particularly, to improved diversity receivers. In some environments, such as those subject to multipath reflection or shadowing, some carriers may be received with low power. In these cases, diversity receivers may provide an improvement of around 3 dB to 6 dB, the latter figure referring to cases where the communication channel is under severe multipath fading and in mobile reception. A diversity receiver effectively comprises two or more separate receivers, or diversity branches, each with its own antenna. Each set of received carriers from each diversity branch is then combined. The present invention provides an improved method and apparatus for receiving multi-carrier signals.

Abstract: The invention relates to a method and circuit arrangement for compensating for an interference component included in a signal in a digital transmission system such as a mobile communication system, radio system or television system. In the method according to the invention a decision error representing an interfering signal is classified using an adaptive method, and a table is drawn up of interference estimates corresponding to classified decision errors. So it is obtained on the basis of previous decision errors an interference estimate corresponding to the next signal sample and that estimate is subtracted from the signal sample before the current decision. The adaptive method is preferably a neural method such as a self-organizing map. With the method according to the invention it is possible to compensate for an interference component in a signal regardless of the interference source assuming that the interfering signal has internal correlation.

Abstract: The invention proposes a method for configuring a network, wherein the network comprises a plurality of network sections, the method comprising the steps of accessing (S2) data from network sections; forming (S3) groups of network sections using a clustering method by using at least part of the accessed data as input data; and processing (S4) parameter on network section group level. By this method, the operation load during optimising a network consisting of a large number of cells can be greatly reduced. The invention also proposes a corresponding network optimising system.

Abstract: A receiver 100 for receiving a multi-carrier signal comprises detection means for detecting 801 the presence of impulse interference within the signal and identifying one or more samples of the signal affected by the impulse interference, means for selecting samples to be blanked, means for blanking the selected samples and means 805 for estimating the blanked signal. The selected samples comprise those samples (l0 to l0+k) identified as being affected by impulse interference and at least one of the following: a number of samples x1 preceding the said identified samples (l0 to l0+k) or a number of samples x2 following the said identified samples (l0 to l0+k). The blanking means may define the length of a blanking window 301 to have one of a plurality of different predetermined lengths, using the smallest of the predetermined lengths sufficient to encompass the selected samples.