Abstract: This disclosure provides a base station for a cellular network, and a method of operating the base station in the cellular network, the cellular network also including a second base station, wherein the first and second base stations include first and second oscillators providing a first and second periodic timing pulse respectively, the method including determining a relative timing offset between a first instance of the first periodic timing pulse for transmission of a frame from the first base station and a first instance of the second periodic timing pulse for transmission of a frame from the second base station; determining that the relative timing offset is changeable; and adjusting the first periodic timing pulse to maintain the relative timing offset by varying a first period between instances of the first periodic timing pulse such that the rate of change of the relative timing offset over time is reduced.

Abstract: A mobile terminal in a wireless communications system estimates channel characteristics from transmissions of a base station comprising reference symbols arranged in a first density and distribution. In the event of an impairment in accuracy of channel estimation, the mobile terminal first applies a checking function to determine whether a base station identity conflict is present. If such a conflict is detected, it transmits a report to the base station to initiate a network channel reallocation process to remove the conflict. If no conflict is detected, the base station is instructed to initiate a function to change the density and distribution of the reference symbols. This allows a dynamic system to distinguish between different causes of poor channel quality, allowing adaptation of the transmissions of the base stations in a manner appropriate to the cause identified.

Abstract: A wireless communications network is configured to transmit signals including a plurality of data units containing reference signals for use in channel assessment by mobile stations receiving the transmissions. Topological data relating to the relative positions of each base stations in the network is used by a density adjustment function to select a distribution pattern and density of reference signals. A signal is sent to one or more user terminals, the signal comprising reference signals arranged in the selected distribution and density of plurality of data units, and including a control signal to indicate to the mobile terminal which density and distribution is in use.

Abstract: A base station in a wireless communications network is configured to transmit signals including a plurality of data units, and selecting for transmission a signal configuration including a distribution pattern of reference signals arranged in a predetermined pattern in the data units with a predetermined density. The signal configuration also includes control data indicative of the reference signal density and distribution. A mobile terminal uses the control data to identify the reference signal density and distribution in use by the base station to which it is working or about to hand over, so that it can identify which symbols are appropriate to estimate the channel characteristics. By adapting the symbol density to local circumstances, in particular the likelihood of Doppler spreading, a more reliable acquisition of the base station can be obtained.

Abstract: A wireless communications network is configured to transmit signals including a plurality of data units containing reference signals for use in channel assessment by mobile stations receiving the transmissions. Topological data relating to the relative positions of each base stations in the network is used by a density adjustment function to select a distribution pattern and density of reference signals. A signal is sent to one or more user terminals, the signal comprising reference signals arranged in the selected distribution and density of plurality of data units, and including a control signal to indicate to the mobile terminal which density and distribution is in use.

Abstract: This disclosure provides a device and method of aligning a transmission frame in a Time Division Duplexing network, wherein the transmission frame includes a sequence of units separated by transition points, wherein each unit includes one or more resource slots in a transmission direction, the method comprising: allocating a transmit power level to a plurality of resource slots in a unit, wherein a transmit power for a first resource slot of the plurality of resource slots is greater than the transmit power for a second resource slot of the plurality of resource slots; measuring the transmit power of a TDD transmission received from an external node to determine a peak transmit power of the received TDD transmission; and substantially aligning the first resource slot to coincide with the peak transmit power of the received TDD transmission.

Abstract: A base station in a wireless communications network is configured to transmit signals including a plurality of data units, and selecting for transmission a signal configuration including a distribution pattern of reference signals arranged in a predetermined pattern in the data units with a predetermined density. The signal configuration also includes control data indicative of the reference signal density and distribution. A mobile terminal uses the control data to identify the reference signal density and distribution in use by the base station to which it is working or about to hand over, so that it can identify which symbols are appropriate to estimate the channel characteristics. By adapting the symbol density to local circumstances, in particular the likelihood of Doppler spreading, a more reliable acquisition of the base station can be obtained.

Abstract: A mobile terminal in a wireless communications system estimates channel characteristics from transmissions of a base station comprising reference symbols arranged in a first density and distribution. In the event of an impairment in accuracy of channel estimation, the mobile terminal first applies a checking function to determine whether a base station identity conflict is present. If such a conflict is detected, it transmits a report to the base station to initiate a network channel reallocation process to remove the conflict. If no conflict is detected, the base station is instructed to initiate a function to change the density and distribution of the reference symbols. This allows a dynamic system to distinguish between different causes of poor channel quality, allowing adaptation of the transmissions of the base stations in a manner appropriate to the cause identified.

Abstract: This disclosure provides a base station for a cellular network, and a method of operating the base station in the cellular network, the cellular network also including a second base station, wherein the first and second base stations include first and second oscillators providing a first and second periodic timing pulse respectively, the method including determining a relative timing offset between a first instance of the first periodic timing pulse for transmission of a frame from the first base station and a first instance of the second periodic timing pulse for transmission of a frame from the second base station; determining that the relative timing offset is changeable; and adjusting the first periodic timing pulse to maintain the relative timing offset by varying a first period between instances of the first periodic timing pulse such that the rate of change of the relative timing offset over time is reduced.

Abstract: Embodiments herein provide systems and methods for sending broadband data to end-users over a DTTV broadcast transmission. Systems and methods for receiving such data are also described. A wireless overlay system is set up by an Internet Service Provider/Communications Provider (ISP/CP) 11 by means of receiving from end-user equipment 27 data requests over a DSL uplink together with identification of at least one DTTV transmitter 21 23. The ISP/CP 11 provides an overlay controller 26 which causes routing of the requested data over a selected DTTV transmitter 21. At the end-user equipment, the requested data can be received from the DTTV broadcast and extracted for output.

Abstract: This disclosure provides a device and method of aligning a transmission frame in a Time Division Duplexing network, wherein the transmission frame includes a sequence of units separated by transition points, wherein each unit includes one or more resource slots in a transmission direction, the method comprising: allocating a transmit power level to a plurality of resource slots in a unit, wherein a transmit power for a first resource slot of the plurality of resource slots is greater than the transmit power for a second resource slot of the plurality of resource slots; measuring the transmit power of a TDD transmission received from an external node to determine a peak transmit power of the received TDD transmission; and substantially aligning the first resource slot to coincide with the peak transmit power of the received TDD transmission.

Abstract: Embodiments herein provide systems and methods for sending broadband data to end-users over a DTTV broadcast transmission. Systems and methods for receiving such data are also described. A wireless overlay system is set up by an Internet Service Provider/Communications Provider (ISP/CP) 11 by means of receiving from end-user equipment 27 data requests over a DSL uplink together with identification of at least one DTTV transmitter 21 23. The ISP/CP 11 provides an overlay controller 26 which causes routing of the requested data over a selected DTTV transmitter 21. At the end-user equipment, the requested data can be received from the DTTV broadcast and extracted for output.

Abstract: The present invention relates to a system for allocating unused radio frequency spectrum channels in shared spectrum bands such as TV Whitespace. A spectrum manager is arranged to maintain a historic profile of available channels in a given area in order to provide predications of channel quality behaviour to devices which request spectrum for data transmission.

Abstract: MIMO OFDM receiver which periodically forms a channel estimate and compares: a: an estimate of the capacity of the channel if the transmitter were to make use of the receiver's channel estimate (closed loop) with b: an estimate of the capacity of the channel if the transmitter were to make no use of channel estimate (open loop), and send data on the channel estimate to the transmitter only when (b?a)>k, where k is a pre-set threshold.

Abstract: The demodulation process of a wireless data transmission system using multi-level symbols makes use of templates corresponding to each of the possible symbol transitions, so that knowledge of previously decoded symbols can be use to decode the next one. The weighting and/or timing of individual samples of each symbol is varied in response to the performance of the symbol identification process.