Northern Telecom Limited

Stc, Inc

Nortel Networks Corporation

Jeffrey G Searle

Stuart James Dean

Peter John Chrystie

Christopher R Cox

Keith Roy Broome

Stephen J Westlake

Keith Russell Edwards

Francis Giles Overbury

Christopher R Ward

Paul Barton

A radio communication system ( ) is disclosed which comprises a base station ( ) for transmitting and receiving signals to and from one or more remote stations ( ). The base station ( ) is provided with at least one receive antenna ( ) coupled to a base station receiver. The receive antenna ( ) is provided with a directional pattern in a horizontal plane and a mechanism for steering the directional pattern azimuthly, until such time as a synchronization signal transmitted by a remote station located within the coverage area is received by the base station receiver. Upon detection of the synchronization signal, scanning of the receive antenna's pattern is stopped until such time as message information can be obtained from the remote station ( ) and forwarded to a particular destination requested by the remote station. Upon receiving the information, the base station ( ) will resume scanning of the antenna ( ), and the information will be forwarded to its requested destination.

Beamed antenna system

A base station antenna arrangement comprising a plurality of antenna arrays each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the totality of beams formed by the arrays provides a substantially omni-directional coverage in azimuth, azimuth and elevation beamforming means for each array, a plurality of r.f. transceivers each for transmitting and receiving r.f. signals for one or more calls, switching matrix means for connecting each transceiver with one or other of the arrays via the beamforming means, control means for controlling the switching matrix means whereby a particular transceiver is connected to a particular array via the beamforming means to exchange r.f. signals with a remote station located in the area covered by one of the narrow beams.

Base station antenna arrangement

An antenna arrangement (10) for a cellular radio base station is provided with a plurality of r.f. transceivers, including one or more antenna arrays (12) each comprising a plurality of sub-arrays (20) each selectively operpable to form a beam in azimuth. Each sub-army is provided with elevation beamforming means (24) and individual transmit and receive amplifiers (30,32). Each sub-array beamformer is coupled to at least one r.f. transmitter feed (26)nd each r.f. receiver feed is coupled to at least two sub-array beamformers, the sub-arrays of each antenna array together forming a multiplicity of separate substantially coincident beams in azimuth. A method of operation is also disclosed.

An antenna for a base station comprising a plurality of antenna arrays (40; FIG. 6a) each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the beams formed by the arrays provide a coverage in azimuth wider than each array. Means are provided for splitting (58; FIGS. 14b,14c) the transmission output of a given transceiver into two signals prior to transmission power amplification and transmitting said signals in two adjacent narrow overlapping beams.

An antenna for a base station comprising a plurality of antenna arrays (40; FIG. 6a) each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the of beams formed by the arrays provide a coverage in azimuth wider than each array. Means are provided for recognizing unique identifier signals (70; FIG. 6b) incorporated in call signals passing through the antenna; and coherent detection means for discriminating between unwanted call signals and wanted call signals using said unique identifier signals.

A smart antenna for a base station comprises a plurality of antenna arrays each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the totality of beams formed by the arrays provides a substantially omni-directional coverage in azimuth A plurality of r.f. transceivers is provided each for transmitting and receiving r.f. signals for one or more calls, with switching matrix means for connecting each transceiver with one or other of the arrays via beamformers. Each transceiver is connected by a switch matrix to a particular array to exchange r.f. signals with a remote station located in the area covered by one of the narrow overlapping beams. Means are provided for selecting for a given call more than one of the best received signals from the multiplicity of narrow overlapping beams and the selected signals are combined to form a single receive signal input for the r.f. transceiver for the given call.

An antenna for a base station comprising a plurality of antenna arrays (40; FIG. 6a) each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the of beams formed by the arrays provide a coverage in azimuth wider than each array. Means (54; FIG. 6a) are provided for independent adjustment of receiver gain and/or transmitter radiated power level of individual beams.

An antenna for a base station comprising a plurality of antenna arrays (40; FIG. 6a) each capable of forming a multiplicity of separate overlapping narrow beams in azimuth, the arrays being positioned such that the beams formed by the arrays provide a coverage in azimuth wider than each array. Means are provided for communication with a base station network whereby communication link means (77; FIG. 5) are provided for communication with a base station network whereby, in addition to telecommunications message traffic passing through the antenna, control and supervisory information can be exchanged between the antenna and the base station network.

An adaptive antenna array arrangement for a receiver in a frequency hopped spread spectrum system. The arrangement includes an auxiliary local oscillator (lo.sub.a) which is hopped sequentially and pseudo-randomly across the spread system independently of the main frequency hopped oscillator (Lo.sub.m). The adaptive array processor (FUA, FM, PM) is digital, operates in an open loop configuration and evaluates the frequency bands during periods of time when the main oscillator is not operating in those bands. The processor derives null sterring weights for each band. The weights for each band are stored (WS) and subsequently used (W.sub.In -W.sub.Qn) when the main oscillator hops into the band and so cause the array of generate nulls directed towards sources of unwanted systems.

Adaptive antenna arrays for frequency hopped systems

An adaptive filter may be realized by weighting the outputs from a tapped delay line. This, however, allows nulls to corrupt a wanted signal spectral region. A fixed (non-adaptive) filter (2) coupled between the signal input and an input of means (3) for summing the weighted outputs serves to allow nulls only to be formed in the skirt region of the fixed filter response thus preserving a wanted signal.

Adaptive filter

A steered adaptive antenna arrangement including an adaptive beamforming network 10 to which the output signals of an array of antenna elements are applied, the network having a feedback wherein the summed output of the network is correlated with each element signal, applied to a limiter and added to the steering component whereby the derived value is used to drive the associated weight coefficient, characterized in that the summed output of the beamformer network 10 is further applied to a desired signal estimator 11 the output of which is subtracted from the summed output to provide the feedback input 12 to be correlated with each element signal.

Growing community of inventors

Galmpton, United Kingdom

Jeffrey G Searle