Abstract: A transceiver used in a radio unit for wireless communication, comprises: a circuitry board including a transmitter and a receiver; a first connector on a first side of the circuitry board, wherein the first connector is configured to be connected to an interface card; a second connector on a second side of the circuitry board, wherein the second side is opposite the first side and the second connector is configured to be connected to a digital card via a flexible circuit; and a pair of transmit port and receive port located on the second side of the circuitry board, wherein the transmit port is coupled to the transmitter and the receive port coupled to the receiver, respectively. When the transceiver is part of a split-mount radio unit (SRU), the first connector is connected to the interface card and the second connector is not in use. When the transceiver is part of an all-outdoor radio unit (AOU), the second connector is connected to the digital card and the first connector is not in use.

Abstract: An outdoor radio communication system comprises a first radio unit, a second radio unit, and a single cable coupling the first radio unit to the second radio unit. Each radio unit includes a downconverter, a radio processor that is communicatively coupled to the downconverter, and a XPIC module. The cable further includes a first twisted-pair of wires for communicatively coupling the first downconverter to the second XPIC module and a second twisted-pair of wires for communicatively coupling the second downconverter to the first XPIC module. The first XPIC module generates a first reference signal using a signal from the second downconverter to cancel cross-polarization interference in an output signal of the first radio processor. Similarly, the second XPIC module generates a second reference signal using a signal from the first downconverter to cancel cross-polarization interference in an output signal of the second radio processor.

Abstract: A transceiver used in a radio unit for wireless communication, comprises: a circuitry board including a transmitter and a receiver; a first connector on a first side of the circuitry board, wherein the first connector is configured to be connected to an interface card; a second connector on a second side of the circuitry board, wherein the second side is opposite the first side and the second connector is configured to be connected to a digital card via a flexible circuit; and a pair of transmit port and receive port located on the second side of the circuitry board, wherein the transmit port is coupled to the transmitter and the receive port coupled to the receiver, respectively. When the transceiver is part of a split-mount radio unit (SRU), the first connector is connected to the interface card and the second connector is not in use. When the transceiver is part of an all-outdoor radio unit (AOU), the second con vector is connected to the digital card and the first connector is not in use.

Abstract: An outdoor radio communication system comprises a first radio unit, a second radio unit, and a single cable coupling the first radio unit to the second radio unit. Each radio unit includes a downconverter, a radio processor that is communicatively coupled to the downconverter, and a XPIC module. The cable further includes a first twisted-pair of wires for communicatively coupling the first downconverter to the second XPIC module and a second twisted-pair of wires for communicatively coupling the second downconverter to the first XPIC module. The first XPIC module generates a first reference signal using a signal from the second downconverter to cancel cross-polarization interference in an output signal of the first radio processor. Similarly, the second XPIC module generates a second reference signal using a signal from the first downconverter to cancel cross-polarization interference in an output signal of the second radio processor.

Abstract: A novel phase detector for use in a timing recovery circuit of pulse amplitude modulation communication system. A filter internal to the phase detector as preliminary stage for operating on a signal stream of pulse-shaped symbols to reduce pattern-dependent jitter of the output of the phase detector. The filter may have plural taps, delays, multipliers, and summers.

Abstract: Method and filters for reducing the number of circuit components and/or the operating speed of the components of a filter used to shape digital transmit symbols for conversion to analog modulation communication systems. A digital signal is processed using M circuit stages. The stages multiply a delayed digital signal and a further delayed digital signal with a corresponding filter coefficient. The output signals of the stages are multiplexed to provide shaped digital transmit symbols. The stages are configured to reduce the number of circuit components and/or operating speed.

Abstract: A slope detector and method of detecting a slope of the passband signal spectrum in a quadrature amplitude modulation (QAM) digital radio system. The detector operates in baseband for comparing signal output powers of upper and lower sidebands of a received passband signal. The slope detector includes transversal filters for filtering I and Q channel inputs and multipliers and combiners for processing the filter outputs to provide an output that is indicative of the slope of the passband signal spectrum. The output may be a value that is translated to an instantaneous slope, or may be tri-state and indicate whether the slope is positive, zero, or negative.