Abstract: A system and method is provided for adaptive downlink beamforming in a wireless communication system. The technique involves using an antenna array to transmit downlink control signals from the base station to the subscribers in the cell. Rather than transmitting the control signals in a given direction continuously, the control signals in the present system are transmitted for only a short time interval using one of a sequence of specified directional beams. After a predetermined sweep cycle period, the control signal beam is then retransmitted again in the same direction. Typically, during this cycle period control signal beams are also transmitted in other specified directions. In one embodiment, for example, the control signal beams sweep around the base station once during each cycle. A subscriber located in the cell will receive a repeating pattern of signal pulses corresponding to the periodic beams directed toward the subscriber.

Abstract: A cost effective electronically self optimizing antenna system is provided for use with each subscriber unit in both fixed and mobile wireless applications. The smart antenna consists of multiple antenna elements arranged so that individual beams independently cover sections of free space. Collectively, complete coverage of the desired free space is accomplished. The smart antenna uses a relatively narrow beam directed in the appropriate direction thereby reducing interference and improving system capacity. A controller is included which continuously monitors the signal quality and intelligently selects the optimum antenna beam pattern configuration. All telecommunication protocols, both analog and digital, can be accommodated by the controller.

Abstract: Outputs of A/D converters 110, 111, and 112 are input to correlation devices 117, 118, and 119. The correlation devices 117, 118, and 119 output ratios of these signals to an output signal of a modulator 116 for modulating an output of a switching device 115. Each of standardizing devices 120, 121, and 122 cancels a gain component from an input signal, and selects a signal having a maximum signal-to-interference power ratio. A switching device 124 switches a transmitting antenna in accordance with the selection result so as tc send a transmitting message. A switching device 125 switches a unique word in a synchronous burst, and a unique word in a communication channel signal, or a receiving message to be sent to the correlation devices as a reference signal.

Abstract: An apparatus and method for selecting between a plurality of antennas utilized by a microcellular communications terminal for reception of a signal, wherein a gain imbalance exists between the antennas.

Abstract: A transmitter is provided in a base station which communicates with a mobile station of a high-speed communication user and a mobile station of a low-speed communication user according to a spread spectrum system. The transmitter includes a first antenna having a wide directivity, a second antenna having a directivity narrower than that of the first antenna, a first transmission unit for transmitting a first transmission signal from the first and second antennas to the mobile station of the low-speed communication user, and a second transmission unit for transmitting a second transmission signal from the second antenna to the mobile station of the high-speed communication user.

Abstract: Diversity and inter-frequency mobile-assisted handoff (MAHO) are achieved under continuous reception cellular access methods by using strategic timing and switching optimizations. Strategic timing is achieved by avoiding the non-reception of power control bits. For example, the mobile terminal can make measurements for diversity in the last eight bits of a sub-frame of an IS-95 downlink transmission. Switching is optimized, for example, by storing rake taps for a first antenna prior to switching to a second antenna so that the rake tap positions can be restored upon returning to the first antenna. With these and other disclosed measurement techniques, the benefits of diversity and inter-frequency MAHO can be achieved in continuous reception cellular systems.

Abstract: A base station equipment for receiving and transmitting a signal of a desired user, which signal to be received may arrive at the equipment along several different paths with several different delays, and which equipment includes one or more antenna arrays composed of several elements, one or more channel units having components for phasing the signal to be transmitted and received by the antenna array in such a way that the gain from the antenna array is the greatest in the desired directions. Each channel unit includes components for searching for the incoming directions and delays of the received signal components, and components for controlling the phasing components on the basis of the information in such a way that the angle of the greatest gain of the antenna beams is deflected in the environment of the desired directions.

Abstract: A dual LNB/TV antenna multi-switch allowing DC voltage provided by a satellite receiver to travel through the terrestrial antenna input without causing interference, distortion or lowering the signal strength of the satellite and terrestrial antenna pictures. By including an external DC block adapter with the invention, the multi-switch can be used with both amplified and non-amplified antennas and not require an external power injector.

Abstract: A process which adjusts the transmission and reception chains of the paths formed by a base station of a system for radio communication between mobiles which after calibration of the antenna base adjusts the reception chains relating to each path by distributing a first specified adjustment signal synchronously over each of the reception chains and calculating an equalization filter which inverts the transfer functions related to each reception chain. The process next adjusts the transmission chains related to each path by distributing a second specified adjustment signal synchronously over each of the transmission chains, by extracting from each of the paths a part of a transmission signal before the transmission signal is sent to the antenna base so as to re-inject that part of the transmission signal into the reception chains, and by calculating an equalization filter which inverts the transfer functions related to each transmission chain.

Abstract: A frequency diversity system for use in mobile reception of television and RF signals in the meter or decimeter wavelength, such as for use with a mobile television having a first receiver, an additional receiver and a control and analysis circuit. The additional receiver detects all incoming frequencies corresponding to a preset program and switches the main receiver to an incoming frequency of a higher quality. The receiver is able to identify the frequencies corresponding to the desired program through a transmitter identification code, which is added to each signal. This code is usually a VPS identification signal. The control and analysis circuit compares the incoming frequencies to the frequency of the signal transmitted by the television receiver to determine the highest quality signal. In order to accelerate the process, the system processes local position coordinates of the television so that the frequencies analyzed are only those expected within the coverage area of the television.

Abstract: Weighting coefficients for a phased array antenna are iteratively refined to optimal values by a ‘bootstrapped’ process that starts with a coarse set of weighting coefficients, to which received signals are subjected, to produce a first set of signal estimates. These estimates and the received signals are iteratively processed a prescribed number of times to refine the weighting coefficients, such that the gain and/or nulls of antenna's directivity pattern will maximize the signal to noise ratio. Such improved functionality is particularly useful in association with the phased array antenna of a base station of a time division multiple access (TDMA) cellular communication system, where it is necessary to cancel interference from co-channel users located in cells adjacent to the cell containing a desired user and the base station.

Abstract: In a diversity receiving system for receiving modulated RF signals using an array of antennas and recovering information signals from the modulated signals, the information signal of the highest strength is selected to allow a connection to be established from a transmit site. Strength data of the selected signal is stored in a corresponding one of memory locations respectively mapped to the antennas. Strength data stored in the memory locations are analyzed. If none of the strength data exceeds a threshold value, a first alarm is given of the whole array of antennas. If at least one strength data exceeds the threshold, the memory locations are tested to see if there is at least one vacant memory location which contains no strength data. If such a vacant location exists, a second alarm is given of the antenna that is mapped to the vacant location.

Abstract: A radio communication apparatus which can cope with a plurality of different communication systems automatically selects a communication system exhibiting good communication channel quality from the plurality of communication systems, thereby performing communication. Communication channel qualities are compared with each other on the basis of at least one of a reception signal electric field strength, a reception data quality signal, and a reception data error rate which are received from each radio base station, or upon assigning priorities thereto, thereby determining a communication system.

Abstract: A micro-diverse directional transmitting antenna array positioned proximately upon the boundary of a convex shape whereby the primary attenuation lobes of neighboring antennae overlap. Distinct transmissions by distinct directional antenna components utilize the same channel resources using transmitting directional antenna components that are not adjacent. Further, a micro-diverse directional antenna array comprising both transmitting and receiving directional antenna components positioned proximately upon the boundary of a convex shape whereby the primary attenuation lobes of nearest neighbor transmitting directional antenna components overlap and the primary attenuation lobes of nearest neighbor receiving directional antenna components overlap.

Abstract: A signal transmitting/receiving method and apparatus freed of the drawback of the conventional information multiplexing method (FDMA, TDMA or CDMA) that information multiplexing needs a bandwidth broader than the bandwidth of the original information, such that, if the bandwidth is scanty, the number of channels that can be accommodated is decreased. A signal transmission device 10 sends three different items of the transmission information, namely the transmission information items TA, TB and TC, from three transmitters 11A, 11B and 11C, by multiplexing communication via three different paths PA, PB and PC, using a transmission antenna unit 12. A signal receiving device 20 receives the three different information items TA, TB and TC, transmitted via three different paths PA, PB and PC, by receivers 22A, 22B, 22C, using a receiving antenna unit 21, for obtaining three different items of the reception information, namely the reception information items RA, RB and RC.