Abstract: The present invention provides methods and apparatus for MIMO communications across wireless fixed links, comprising a first pair of dual polar antennas, spaced apart in a direction orthogonal to the direction of the fixed link for transmission, and a second such pair for reception, wherein orthogonal polarisations of one of each pair of antennas are oriented intermediate between the orthogonal polarisations of the other of each pair of antennas.

Abstract: A method of associating the Training code to a Channelisation code in a mobile telecommunications system. The method includes associating a Training code with a Channelisation code prior to transmission according to a set of rules such that upon detection of the Training code by a receiver, the Channelisation code is known.

Abstract: Described herein is a method of providing synchronization between a plurality of base stations (300) in a telecommunications system which comprises providing a random access channel in each cell (320). A local base station (300) uses the random access channel in the local cell to transmit a synchronization signal to neighboring base stations. For each base station, the time differences between received synchronization signals from neighboring base stations and the local synchronization signal are calculated. Each set of time differences is either used to autonomously synchronize the local base station or is centralized in a radio network controller and a set of corrections distributed from the RNC to the base stations.

Abstract: A method determines the position of a mobile object by using at least one radio signal having a rotating transmission characteristic with at least one reference station. The relation between the orientation of the transmission characteristic and reference events is communicated to the mobile object. The orientation of the transmission characteristic and the relative position with respect to the reference station can be determined from the reference event.

Abstract: A packet radio system is provided with a multiple access scheme which operates to schedule transmissions of data bearing radio packets on a common communications channel from a plurality of users to a common receiver of the said system. The radio packets via which the plurality of users communicate include synchronization data, and by providing the common receiver with a multi-user detector, contemporaneously transmitted packets may be detected and recovered in dependence upon the synchronization data, thereby substantially increasing a throughput of the packet radio system.

Abstract: A method and apparatus for use in a packet radio system is provided wherein a time for providing a plurality of users of the system with acknowledgement data appertaining to successful transmission of packets of data bearing radio signals is large in comparison with a rate of demand for communication of data, and wherein authorisation for transmission of packets is based on an estimate of a number of active users. The method and apparatus provides the users with an estimate of the number active users, calculated in accordance with an average number of acknowledgements received during a predetermined time.

Abstract: A communication system wherein known data sequences characterize both wanted transmitted signals and interfering co-channel transmitted signals, comprising a receiver for receiving a wanted transmitted signal in the presence of unwanted co-channel interfering signals. The receiver comprises a signal sequence identifier means which includes a memory for known data sequences and a correlator which serves to correlate received signals with the stored known data sequences, whereby the relative location in time of received signal sequences is identified.