Abstract: An Automatic Gain Control (AGC) module for controlling Noise Figure (NF) and IM characteristics therein is disclosed. The AGC module comprises a plurality of AGC stages. Each AGC stage comprises a differential amplifier circuit, an input signal transistor and a current-steering circuit. Differential amplifier circuits of the plurality of AGC stages receive control signals at their differential inputs and their output is connected to a common load. The input signal transistors of the plurality of AGC stages receive a common input signal and is further coupled to the differential amplifier circuit and the current-steering circuit. The current-steering circuits and the control signals at the differential amplifier circuits control gain of the each AGC stage of the plurality of AGC stage, which is used to control the NF and the IM characteristics.

Abstract: A quadrature frequency changer comprising first and second mixers and a local oscillator and a tuner and modulator including the quadrature frequency changer are provided. The local oscillator provides first and second commutating signals which are nominally in phase-quadrature and includes an arrangement for changing the phase of the first commutating signal by 180° to provide a third commutating signal. The first mixer comprises first and second mixing stages for mixing an input signal with the first and second commutating signals and a summer for summing the mixer stage output signals. The second mixer comprises third and fourth mixing stages for mixing the same or a different input signal with the second and third commuting signals and a summer for summing the third and fourth mixer stage output signals.

Abstract: An Automatic Gain Control (AGC) module for controlling Noise Figure (NF) and IM characteristics therein is disclosed. The AGC module comprises a plurality of AGC stages. Each AGC stage comprises a differential amplifier circuit, an input signal transistor and a current-steering circuit. Differential amplifier circuits of the plurality of AGC stages receive control signals at their differential inputs and their output is connected to a common load. The input signal transistors of the plurality of AGC stages receive a common input signal and is further coupled to the differential amplifier circuit and the current-steering circuit. The current-steering circuits and the control signals at the differential amplifier circuits control gain of the each AGC stage of the plurality of AGC stage, which is used to control the NF and the IM characteristics.

Abstract: In some embodiments, a radio transmitter assembly comprises a test signal generator module to generate a first instance of a test signal, the test signal comprising a code, a test signal receiver module which receives the code, a signal combiner to combine the first instance of the test signal with a real signal to create a combined signal, a radio signal generator to generate a radio signal from the combined signal, a signal separator to separate a second instance of the test signal from the radio signal, and comparator logic in the test signal receiver module to compare the code with a code embedded in the second instance of the test signal in the test signal receiver module.

Abstract: Techniques are described that can be used to reduce interference in a desired channel by one or more other channels. A radio includes a level detect logic that is responsive to both the frequency offset and amplitude of undesired signals and sets the gain applied to received signals based on the offset frequency and determined amplitude of undesired signals. For example, detection of a signal amplitude in an interfering signal in a channel adjacent to the desired channel may be made. Detection of a signal amplitude in an interfering signal in a channel other than the adjacent channel and desired channel may also be made. Based on detection of one or more interfering channel, a gain of an input signal may be adjusted. Interference arising from at least spectral re-growth of noise and clipping noise may be reduced.

Abstract: Embodiments of a zero intermediate frequency (ZIF) tuner are described generally herein. Other embodiments may be described and claimed.

Abstract: A pulse generator is provided for generating pulses with a selectable variable width and/or delay. The pulse generator comprises an oscillator and a selecting arrangement for selecting how many of a first group of delay elements are connected in series for delaying the oscillator signal. Identical delay elements are connected in series to form a second group. A measuring circuit repeatedly measures the delay provided by the second group, for example providing output pulses whose width or duration is equal to the delay. A reference pulse generator generates a series of reference pulses, each of which is a predetermined fraction of the oscillator period. A control circuit compares the measurement and reference pulses to generate an error signal that is fed back to timing delay control inputs of all the delay elements such that the widths of the measurement and reference pulses are made substantially equal to each other.

Abstract: A pulse generator is provided for generating pulses with a selectable variable width and/or delay. The pulse generator comprises an oscillator and a selecting arrangement for selecting how many of a first group of delay elements are connected in series for delaying the oscillator signal. Identical delay elements are connected in series to form a second group. A measuring circuit repeatedly measures the delay provided by the second group, for example providing output pulses whose width or duration is equal to the delay. A reference pulse generator generates a series of reference pulses, each of which is a predetermined fraction of the oscillator period. A control circuit compares the measurement and reference pulses to generate an error signal that is fed back to timing delay control inputs of all the delay elements such that the widths of the measurement and reference pulses are made substantially equal to each other.

Abstract: A quadrature frequency changer comprising first and second mixers and a local oscillator and a tuner and modulator including the quadrature frequency changer are provided. The local oscillator provides first and second commutating signals which are nominally in phase-quadrature and includes an arrangement for changing the phase of the first commutating signal by 180° to provide a third commutating signal. The first mixer comprises first and second mixing stages for mixing an input signal with the first and second commutating signals and a summer for summing the mixer stage output signals. The second mixer comprises third and fourth mixing stages for mixing the same or a different input signal with the second and third commuting signals and a summer for summing the third and fourth mixer stage output signals.

Abstract: A frequency changer for a radio frequency tuner and a tuner incorporating such a frequency changer are provided. The frequency changer comprises a mixer comprising a plurality of mixing stages. The output signals of these stages are supplied without relative phase shift to a summer, for example, in the form of a common load arrangement. The inputs of the stages are connected together to form a signal input of the mixer. Commutating signal inputs of the mixing stages received from the local oscillator are of the same frequency, but of different phases. The commutating signals are square or rectangular waves.