Abstract: A method of video encoding including receiving a video signal to be coded; coding data representing a frame of said video signal; and repeating part, but not all, of the data. The repeated part including the picture header for the frame. A method of decoding an encoded video signal including receiving coded data representing frames of a video signal; examining the coded data to detect header data and picture data; when an error in the picture header is detected, storing the picture data in a temporary picture data store, detecting a repeat of the header data; and decoding the stored picture data using the repeated header data.

Abstract: A method of encoding a video signal representing a sequence of pictures, the method employing both non-temporal prediction and temporal prediction, wherein the method comprises, for each picture that forms a reference picture for the temporal prediction of another picture, associating with each such picture an indicator indicating the temporal order of the reference picture in the encoded video signal relative to the other reference pictures in the encoded video signal.

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 present invention relates to receivers such as multi-carrier receivers. An orthogonal frequency division multiplex (OFDM) receiver in a terrestrial digital video broadcast (DVB-T) network is required to operate in a complex channel environment, wherein high power analogue television signals may co-exist. The mix of high power analogue television signals and lower power digital signals results primarily from the concurrent existence of both analogue and digital television services. The present invention provides a receiver having improved power efficiency.

Abstract: The invention relates to a digital radio link system and a method of adjusting the transmission power in a digital radio link system. The system comprises at a receiving end a first means for monitoring the error rate estimate and for producing a first control signal if the error rate estimate exceeds a predetermined threshold value. At a transmitting end the system comrises means for adjusting the transmission power, said means responding to the occurrence of the first control signal by increasing the transmission power. In the system of the invention there is further provided at the receiving end a second means for monitoring the rate of change of the received signal level and for producing a second control signal if the rate of change exceeds a predetermined threshold value. The means for adjusting the transmission power respond to the occurrence of the first or the second control signal by increasing the transmission power temporarily close to the maximum transmission power.