Abstract: A base station (28) included in a radio access network of a telecommunications system has two diversity antennas (44A, 44B) for a cell/carrier utilized in a sector served by the base station which are respectively involved in transmission of two branches of a radio link signal of the cell/carrier between the base station and a user equipment unit (30). Two branches of signal processing hardware respectively process the two branches of the radio link signal to yield two respective processed branches of the radio link signal. A rake receiver (62, 262) measures the delay difference between the two processed branches of the radio link signal, and uses the measured delay difference for various purposes. For example, some embodiments of the invention use the delay difference between the two branches as measured by the rake receiver to compensate for a delay difference which exists between the two processed branches of the radio link signal.

Abstract: The present invention is related to a Rake receiver (R1) for receiving a radio signal and to a searcher (S8a, S8b) for estimating the delay profile of one or more radio links. The searcher includes means for estimating delay profiles in separate windows. The searcher is arranged for being switched into a single window mode or alternatively into a multiple window mode. In single window mode the delay profiles of separate radio links are estimated in the windows, while in multiple window mode two or more windows are allocated adjacent in time for estimating the delay profile of the same radio link. Thereby, the use of the resources of the searcher can be adapted to the radio environments in which the searcher will be used. The Rake receiver comprises fingers that are grouped into two sets. Within a set of fingers the propagation paths are time aligned. The output from the two set of fingers are time aligned and then combined.

Abstract: An apparatus and method are described in which a corrected signal-to-interference ratio (SIR) is determined in a cellular telephone receiver. First the estimated signal strength at the receiver is measured, then the estimated interference level is measured. The signal strength and the interference values are separately corrected in accordance with an algorithm. Thereafter, a corrected SIR value is obtained by dividing the corrected signal strength and the corrected interference values.

Abstract: In a Time Division Multiple Access based radio telecommunications system that employs downlink power control, received signal strength information is measured and reported. A downlink data signal is transmitted from a base station to a mobile station during a first timeslot. A control channel signal or a dedicated traffic channel signal having equivalent output power behavior as the control channel, is transmitted from the base station throughout a cell in which the mobile station is operating. At the mobile station, a received signal strength of the control channel signal or the dedicated traffic channel signal is measured. The received signal strength may be measured in period between when the mobile station transmits and receives or in a period between when the mobile station received and transmits. The received signal strength may be measured during the first timeslot or during a timeslot other than said first timeslot.

Abstract: The present invention is directed to cellular systems and methods for providing a multi-beam antenna configuration within a base station without utilizing duplex filters. The multi-beam antenna configuration of the present invention produces overlaid beams in both the uplink and downlink to cover the same area. Each beam has orthogonally oriented polarization directions (e.g., linear polarized slanted ±45°) for the uplink and downlink. Adjacent uplink beams shall also have shifted polarization directions in order to attain polarization diversity between different beams. In order to implement this polarization configuration, for each beam, there is a selective filter in front of the low noise amplifier for the uplink, and no duplex filter in front of the amplifier in the downlink direction.

Abstract: Methods and apparatus for controlling the initial transmit power from a base station to a mobile station at call set-up and call handoff. The initial transmit power from a base station during a call set-up can be reduced from the conventional full power level by a sum of the hysteresis value for the cell which is handing off the mobile station and the hysteresis value for the cell which is receiving the mobile station. When a mobile station initiates or receives a call, the initial transmit power from a base station to the mobile station is reduced from the full power level by the hysteresis value for the hysteresis zone which surrounds the cell in which call set-up is to occur. The reduction in the initial power levels reduces interference caused to surrounding cells at the initiation of a call set-up or call handoff.

Abstract: The present invention is related to a terrestrial cellular radio communication network comprising at least a first base station (BS1) in which a common set of multi carrier power amplifiers (409-412) are used to amplify radio signals transmitted by the first base station (BS1) in different cells. The invention enables reductions in the total maximum output power the first base station (BS1) needs to support when downlink power control functions, such as power control or discontinuous transmission, and/or Adaptive Channel Allocation are applied in the cells served by the first base station (BS1).

Abstract: A telecommunications system and method is disclosed for allowing a base station to simultaneously transmit signals in several beams of a multi-beam antenna configuration. Antenna pattern control is maintained by employing orthogonal polarization orientation for every other beam. For example, the two orthogonal polarization directions can be approximately linear polarization slanted ±45°. To be able to transmit simultaneously in an arbitrary combination of more than one beam, the BS antenna array includes a separate feeder cable for each combination of beams corresponding to a particular polarization, from one feeder per beam to one feeder with all beams of that polarization.

Abstract: A radiocommunication method and system which facilitates half-rate communications as well as downlink power control and selective beam transmission is described. Data associated with two terminals is multiplexed into a single timeslot. A first terminal's data occupies a first portion of the timeslot, while the second terminal's data occupies a second portion of the timeslot. A synchronization/training field may separate the first and second portions of the timeslot. In this way, a base station can change the power level and/or direction of transmission of the different terminal's data even though that data is multiplexed together on the same timeslot.

Abstract: The present invention is related to a Rake receiver (R1) for receiving a radio signal and to a searcher (S8a, S8b) for estimating the delay profile of one or more radio links. The searcher includes means for estimating delay profiles in separate windows. The searcher is arranged for being switched into a single window mode or alternatively into a multiple window mode. In single window mode the delay profiles of separate radio links are estimated in the windows, while in multiple window mode two or more windows are allocated adjacent in time for estimating the delay profile of the same radio link. Thereby, the use of the resources of the searcher can be adapted to the radio environments in which the searcher will be used. The Rake receiver comprises fingers that are grouped into two sets. Within a set of fingers the propagation paths are time aligned. The output from the two set of fingers are time aligned and then combined.

Abstract: Directional beam generative apparatus, and an associated method, for a radio communication station forms directional antenna beam patterns for the communication of communication signals with remote communication stations operable in a TDMA communication system. Channels are allocated for effectuation of communications between the radio communication station and the remote stations responsive to indications of locations at which the remote communication stations are indicated to be positioned. Remote communication stations indicated to be positioned within a selected area are allocated to channels formed upon a single carrier.

Abstract: A digital radio communication system includes processing to jointly mitigate the deleterious effects of fading, time dispersion and interference using interference rejection and diversity combining. The system employs a selection processor for preliminarily reducing the number of signals for interference rejection and diversity combining based on one or more criterion. The system accommodates signals from dual polarized antennas. In one particular embodiment, the system performs interference rejection and diversity combining by separating a received signal into its in-phase and quadrature components.

Abstract: Power control apparatus and an associated method for a transmitting station operable in a TDMA communication system. The transmitting station includes transmitter branches for communicating communication signal bursts during selected time slots. Communication signal bursts transmitted upon adjacent time slots partially overlap so that a receiving station is able to extract information from a communication signal burst transmitted upon an adjacent time slot.

Abstract: A method and apparatus in a radio telecommunications system for converting data from a first sample rate to a second sample rate such that the first and second sample rates are preferably within 10% of each other are disclosed. An input buffer receives a plurality of data groupings at a first sample rate. A spline filter utilizes the input data along with a phase difference between input and output data to calculate a third order spline function and an output time for the input data. This information is used to convert the input data at the first sample rate to output data at a second sample rate. The output data is buffered within an output buffer until transmitted to an associated base band unit.

Abstract: Methods and systems for determining a cosine (I) or sine (Q) component for the purpose of modulating a digital signal in radiocommunication systems are disclosed. Exemplary embodiments describe how such determinations may be performed using digital signal processing techniques to improve component accuracy, while reducing the amount of processor memory (e.g., DSP memory) used to accomplish this task. Phase information from a sampled signal is used to access one or more tables containing component values, or a combination of a component base values and difference values between consecutive base values. The phase information can be used derive an offset value from the difference values, which offset value is added to a component base value to provide a component value for output. This has the effect of reducing the amount of memory consumed while maintaining high resolution.