Motorola Corporation

Motorola Mobility LLC

Gregory T Nash

Thomas J Kundmann

Robert Szopko

Thomas J Kovarik

Aaron W Netsell

Asad U Aman

Steven G Van Gheem

Justin N Annes

A method, a system and a device for implementing a scalable, self-calibrating and configuring, radio frequency head in a wireless base station that performs phase calibration for coherent combining of a pair of transmitter outputs. Configurable Antenna Calibration (CAC) logic initiates phase calibration for coherent combining by selecting a first configuration and triggering the transmission of a reference signal by radio frequency (RF) transmitters using different sub-carriers. The CAC logic generates a vector of phase values by comparing the reference signal with the respective signals received by a calibration receiver. The CAC logic also generates calibration coefficients for coherent combining by normalizing the phase values. In addition, a passive combiner mechanism is employed to implement coherent combining. The CAC logic performs calibration of smart antennas by providing calibration coefficients via a second configuration which utilizes both a calibration transmitter and the calibration receiver.

Scalable self-calibrating and configuring radio frequency head for a wireless communication system

A method, wireless communication device, and a base station calibrate relative phase of a plurality of output signals from respectively combined plurality of transmitters () in the wireless device (). An output of a combiner () is disconnected () from an antenna port () of a wireless device (). A phase position of an output signal from one of the at least two transmitters is set to an initial phase position value (). The phase position of the output signal is incremented by a given phase increment value until a final phase position value is reached (). Occurrences of reverse power alarm events are monitored at the initial phase position value, at each incremental phase position value, and at the final phase position value (). A phase position value for the output signal is selected ().

Phase calibration for multiple transmitter systems

A programmable modulator () is programmable to operate in either of a GMSK or 8PSK mode. When operating in a GMSK mode, a signal modulating circuitreceives () a bit stream (), maps the bit stream () to a phase value in complex I, Q form and applies a progressive rotation to the phase value according to GMSK specifications. The output () is filtered by a filter circuit (), preferably using a complex Finite Impulse Response (FIR) filter using the standard coefficients for an 8PSK modulation to create () an approximate GMSK output (). A GMSK correction circuit () determines a correction term that is added to the filter circuit output () so as to correct amplitude variations to allow the output to conform to GSM/EDGE standards. The same modulator () may be programmed to operate in an 8PSK mode with linear predistortion.

Apparatus and method for modulating and digitally predistorting a signal in a multiple modulation schemes

An interference cancellerand corresponding method thereof operates to reduce the level of an interfering signal and includes a circulatorcomprising a transmitter port, a receiver port and an antenna port, a transmission linecomprising a first end coupled to the transmitter port and a second end for coupling to a signal source; and a circuit, having an input coupled to the receiver portand an output coupledto the transmission line, for providing a phase shifted version of a signal coupled to the input at the output, wherein an interfering signal at the antenna port is reverse coupled to the transmission line by the circulator and coupled to the input of the circuit so as to reduce an amplitude of the interfering signal at the second endof the transmission line. The interference canceller concepts may advantageously be used in a single transmitter version or in a multiple transmitter version (FIG.).

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Arlington Heights, IL, United States of America

Gregory T Nash