Motorola Solutions, Inc.

Jiun How Ng

Shafiullah Syed

Moh Lim Sim

Chong Hin Chee

Christian Ibarra

John R Melton

Dongho Han

A device and method for reducing intermodulation within a radio receiver. The device includes an intermodulation filter. The intermodulation filter is configured to receive a signal, apply a first filter and a second filter to the signal to generate a first and a second filtered signal. The intermodulation filter is configured to isolate a first intermodulation component located on a first side of a frequency spectrum of the signal within the second filtered signal, determine an estimated second intermodulation component based on a potential frequency band location, determine a correction factor based on an amplitude and phase relationship between the first and second intermodulation components, apply the correction factor to the estimated second intermodulation component, determine if the second intermodulation component exceeds a predetermined power threshold, and apply the adjusted estimated second intermodulation component to the first filtered signal, suppressing the second intermodulation component.

Second order interference rejection in a radio receiver

Reducing transient response in a phase-locked loop circuit. In one instance, a system including a phase detector; a cycle slip detector; and a charge pump electrically connected to the phase detector is provided. The charge pump includes an adapt mode charge pump configured to bypass the phase detector with the cycle slip detector when a frequency error surpasses a first error threshold and an instantaneous frequency surpasses a desired frequency threshold. The charge pump also includes an adapt mode, programmable trickle current source configured to provide a ramp-up trickle current to the phase-locked loop circuit.

Reducing transient response in a phase-locked loop circuit

A dual watch receiver is provided that, when operating in a single watch mode, receives a radio frequency (RF) signal, determines a signal quality metric associated with a received RF signal, and based on the determined signal quality metric, determines whether to route a same RF signal to only a first receiver path or to both of the first receiver path and a second receiver path, wherein the first receiver path and second receiver path process a received RF signal in parallel.

Dual watch radio frequency receiver

A current mode receiver front end for a radio device converts a received signal into a current mode signal and applies automatic gain control by both shunting current of the current mode signal and providing an adjustable series resistance that further adjust the current level of the current mode signal that is output by the receiver front end. The shunt and series circuits can be controlled by a digital control word whose value represent a decibel value of adjustment, and which is used to drive the shunt and series circuits to achieve both coarse and fine adjustment of the current mode signal.

Method and apparatus for automatic gain control in a current mode RF receiver

A low-noise amplifier is provided that includes an input amplifier stage coupled to a plurality of independently switchable output amplifier stages. The input amplifier stage is operative to amplify an input communications signal, and it provides both an amplified communications signal and a feedforward signal. The amplified communications signal and the feedforward signal both include a distortion component. Each of the switchable output stages is operative to provide an output that combines the feedforward signal with the amplified communications signal in such a way that the distortion components of the signals at least partially cancel one another. In some embodiments, the switching of the output amplifier stages is performed by circuitry that also serves to improve reverse isolation of the separate output amplifier stages.

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Puchong, Malaysia

Jiun How Ng