Patent ID: 6084545
Filing Date: 2000-07-04
Classification: H01Q

Abstract:
An antenna system, comprising:an transmit antenna array including a signal port and also including a beam conditioning or beam-forming control input port coupled to at least controllable phase shifters;a transmit calibration probe affixed at a nominal location in the near field of said transmit antenna array;transmit antenna switching means including at least common, calibration, and transmit ports, said common port being coupled to said signal port of said transmit antenna array;a source of transmit antenna array calibration signals;transmit antenna array calibration signal coupling means coupled to said source of transmit antenna array calibration signals and to said calibration port of said transmit antenna switching means, for controllably coupling said transmit antenna array calibration signals to said signal port of said transmit antenna array, so that said transmit antenna array calibration signal, when applied to said signal port of said transmit antenna array, is transmitted by said transmit antenna array;calibration encoding means for sequentially generating sets of values, each set of values being orthogonal to other sets of values;transmit antenna encoding signal coupling means coupled to said calibration encoding means and to said beam conditioning control port of said transmit antenna array, for, during calibration, coupling said calibration encoding signals to said beam conditioning control port of said transmit antenna array, for thereby sequentially setting at least some of said phase shifters of said transmit antenna array with said plurality of sets of values, whereby said transmit antenna array calibration probe receives said transmit antenna array calibration signals sequentially encoded with mutually orthogonal values;an receive array antenna including a signal port and also including a beam conditioning control input port coupled to at least controllable phase shifters of said receive array antenna;a receive calibration probe affixed at a nominal location in the near field of said receive antenna array;receive antenna switching means including at least common, calibration, and receive ports, said common port of said receive antenna switching means being coupled to said signal port of said receive antenna array;a source of receive antenna array calibration signals;receive antenna array calibration signal coupling means coupled to said source of receive antenna array calibration signals and to said receive calibration probe, for controllably coupling said receive antenna array calibration signals to said receive calibration probe, whereby said receive antenna array calibration signal is transmitted by said receive calibration probe and is received by said receive antenna array;receive antenna encoding signal coupling means coupled to said calibration encoding means and to said beam conditioning control port of said receive antenna array, for, during calibration, sequentially setting at least some of said phase shifters of said receive antenna array with said plurality of sets of values, whereby said receive antenna array produces, at said signal port, receive antenna array calibration signals sequentially encoded with mutually orthogonal values;a transmit/receive calibration switch including transmit signal port, receive signal port, and a common port, for coupling signals applied to one of said transmit signal port and said receive signal port to said common port;first encoded signal coupling means coupled to said transmit calibration probe and to said transmit signal port of said transmit/receive calibration switch, for coupling said transmit antenna array calibration signals sequentially encoded with mutually orthogonal values to said transmit/receive calibration switch, whereby said transmit antenna array calibration signals sequentially encoded with mutually orthogonal values are produced at said common port of said transmit/receive calibration switch in an transmit antenna array calibration mode of operation;second encoded signal coupling means coupled to said signal port of said receive antenna array switching means and to said common port of said receive antenna switching means, for, in a calibration mode of operation, coupling said receive antenna array calibration signals sequentially encoded with mutually orthogonal values to said calibration port of said receive antenna switching means, whereby said receive antenna array calibration signals sequentially encoded with mutually orthogonal values appear at said calibration port of said receive antenna switching means;third encoded signal coupling means coupled to said calibration port of said receive antenna switching means and to said receive port of said transmit/receive calibration switch, whereby said receive antenna array calibration signals sequentially encoded with mutually orthogonal values are produced at said common port of said transmit/receive calibration switch in an receive antenna array mode of operation;analog-to-digital conversion means including an input port coupled to said common port of said transmit/receive calibration switch, for converting into digital form those analog signals applied to said input port of said analog-to-digital conversion means, to thereby generate a digital version of said transmit antenna array calibration signals sequentially encoded with mutually orthogonal values in said transmit antenna array calibration mode of operation and a digital version of said receive antenna array calibration signals sequentially encoded with mutually orthogonal values in said receive antenna array calibration mode of operation;signal processing means coupled to said analog-to-digital conversion means, for decoding that one of said digital version of said transmit antenna array calibration signals sequentially encoded with mutually orthogonal values and said digital version of said receive antenna array calibration signals sequentially encoded with mutually orthogonal values which is produced by said analog-to-digital conversion means, to thereby generate signals representing the relationship between a bit applied to each of said phase shifters and the resulting phase.