Abstract: An antenna diversity system for receiving frequency-modulated (FM) radio signals with the phase-controlled summation of antenna signals for motor vehicles equipped with a multi-antenna system having at least two antenna output signals, and a receiver with an input for each of a first and a second received signal path, wherein the second of the two received signal paths contains a phase-shifter controlled by a phase-controller. The received signal has the same phase on the output of the phase-shifter as in the first signal path. The two received signals are added up in a phase-coincident manner in a summation circuit, and the added-up signal is supplied to the FM frequency modulator.

Abstract: A radiocommunication system is described wherein a flexible transceiver is provided that can be switchably connected to different antenna structures. Switching matrices are provided between the antenna elements and the receive processing circuitry which, under the control of the central processing unit, allows the transceiver to handle the different antenna structures. The enhanced flexibility achieved by the present invention provides a novel transceiver which can, for example, be reconfigured between and during calls to dynamically assign resources based upon changes in the amount and type of load being experienced by the system and adjusted in order to render existing operating functions more efficient.

Abstract: A phased array spread spectrum system for maximizing signal strength of a spread-spectrum signal with multipath through the use of receiving means, delaying means, combining means, despreading means, generating means, storing means and comparing means. The receiving means receives a plurality of spread-spectrum signals and a plurality of phased versions of the plurality of spread-spectrum signals. The delaying means delays the received plurality of spread-spectrum signals with respect to the plurality of phased versions of the plurality of spread-spectrum signals by a plurality of delays. The combining means combines the delayed spread-spectrum signals and the plurality of phased versions of the plurality of spread-spectrum signals as a plurality of combined signals. The despreading means despreads the plurality of combined signals as a plurality of despread signals. The generating means generates a plurality of magnitude values from the plurality of despread signals.

Abstract: Corresponding to transmission data 101, phase controller 105 is controlled to shift a phase of modulated signal 103 by 0° or 180°. Planes of polarization of modulated signals to be transmitted from antennas 106 and 107 are made different from each other corresponding to transmission data 101. The electric field strength of a signal received at antenna 108 changes corresponding to the plane of polarization, thereby voltage value 113 output from electric field strength detector 111 varies corresponding to transmission data 101, and using this variation, judged result 115 is obtained. Two results, namely, demodulated data 112 and judged result 115 are input to comparing circuit 116, whereby the reception apparatus is capable of obtaining received data 117 with high quality.

Abstract: A transmission side device combines two independent transmission signals (S1, S2) together to produce two combined signals, i.e., a sum signal (S1+S2) and a difference signal (S1−S2), and transmits the produced signals over two radio wave propagation paths, respectively. After the sum signal and the difference signal are received by the reception side device, the sum signal and the difference signal, as received, are subjected to an AGC control operation and a complex-level multiplication operation with a weighting coefficient based on correlation control, and then separated into two, restored, independent signals.

Abstract: A communications system that uses electromagnetic waves. The communications system preferably operates in the millimeter-wave frequencies, and provides relatively high signal restoration and isolation. The communications system can use polarization diversity to increase the capacity of a channel. Isolation and restoration features in the transceivers eliminate or reduce the effects of precipitation and/or reflection and diffraction from objects, and thus is well-suited for an urban environment. The transceiver will select the proper antenna and signal path for optimal information throughput as the conditions in the propagation medium of the network vary.

Abstract: An adaptive reception and transmission technique according to one embodiment of the invention offers the advantages of adaptive reception transmission using feedback without the associated mobile radio complexity increase and information capacity penalty. The technique has been developed to exploit structured variation which occurs in the multipath fading present in the wireless antenna array channel. Thus, multipath propagation effects are explicitly accounted for in the problem approach. The technique is blind in that the antenna beam is formed in the absence of explicit knowledge of the array geometry, and without the necessity of array calibration or mobile feedback. The basic approach is to estimate the optimum receive and transmit antenna beam pattern based on certain statistical properties of the received antenna array signals. The optimum receive and transmit beam pattern is found by solving an optimization equation.

Abstract: A communication station (1) for contactless communication with at least one transponder is provided with a transmission coil configuration (2) with an active, first transmission coil circuit (3) which includes a first transmission coil (4) and with a passive, second transmission coil circuit (7) which includes a second transmission coil (8), and additionally with an active, third transmission coil circuit (11) which includes a third transmission coil (12); in a preferred embodiment a coupling coil (15) is coupled to the second transmission coil (8), first receiving means (32) being connected to the first transmission coil circuit (3) and to the third transmission coil circuit (11) whereas second receiving means (37) are connected to the coupling coil (15), both receiving means (32, 37) delivering received data (RDA) which can be applied to data evaluation means (19).

Abstract: An antenna array portion of a communication device receives a desired signal and an interfering signal. The unweighted desired and interfering signals from a first antenna (302) are then combined in a summer (308) with weighted versions of the signals from a second antenna (304) to produce a received RF signal (312). The signal-to-noise ratio (SNR) of the received RF signal (312) is then estimated using a spectral analysis technique. This estimate, along with the complex weights applied to the signal from the second antenna, is then stored. Utilizing feedback and a methodology for searching through a range of sets of complex weights, the weights optimizing the SNR are determined and used to weight subsequent signals from the second antenna.