Motorola Corporation

Motorola Solutions, Inc.

Kevin J McCallum

Paul H Gailus

Manuel P Gabato

Jeffrey B Wilhite

Leland B Arms

A feedback loop with an adjustable closed loop frequency response. The feedback loop contains adjustable pole () and adjustable zero elements () for changing the pole and/or zero locations in the feedback loop's loop frequency response thereby changing the closed loop frequency response of the feedback loop. In one embodiment, the feedback loop is a Cartesian feedback loop suitable for use in a radio transmitter.

Feedback loop with adjustable bandwidth

An apparatus includes a current generator (,) having an output. A plurality of mixers (,, and,) is switchably coupled to the current generator output, such that a first average power output level is provided when a first mixer (,) of the plurality of mixers is engaged and a second average power output level is provided when a second mixer (,) of the plurality of mixers is engaged. Alternatively, a first average power output level is provided when a first mixer (,) and a second mixer (,) of the plurality of mixers is engaged and a second average power output level is provided when the first mixer (,) of the plurality of mixers is engaged. The first average power output level and the second average power output level are different.

Method and apparatus for selecting from multiple mixers

An apparatus includes a current generator (101) having an output. A plurality of mixers (103, 105, and 107) is switchably coupled to the current generator output, such that a first average power output level is provided when a first mixer (103) of the plurality of mixers is engaged and a second average power output level is provided when a second mixer (105) of the plurality of mixers is engaged. The first average power output level and the second average power output level are different.

An adaptive thermal protection method and arrangement for a power amplifier by remote sense is disclosed which maximizes the amount of output power from electronic equipment such as a radio frequency (RF) power amplifier, having a finite heat sink and operating intermittently over a period of time. This method and apparatus utilizes a remote temperature sensor and knowledge of the on/off, or key/dekey times in conjunction with a stored, predetermined thermal model to adjust the operating power level to a maximum permissible point within a range of operating power levels such that the projected temperature of the power amplifier does not exceed a preset limit. In so doing, the apparatus and method combines the advantages of thermal protection and power maximazation and effects gradual changes in the operating power level by adapting to variable environmental and operational conditions.

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Algonquin, IL, United States of America

Kevin J McCallum