Abstract: A circuit and method for tracking a local oscillator signal frequency in an RF tuner, for tuning input RF signals. The RF tuner includes a frequency-dependent impedance generator that generates a frequency-dependent impedance at the input by rejecting unwanted input RF signals and shunt feeding back the desired signal to the input. The desired signal frequency is centered at the local oscillator signal frequency. The frequency-dependent impedance generator is used with an amplifier circuit to generate a tracking amplifier, the frequency-dependent amplifier gain of which tracks the local oscillator signal frequency.

Abstract: The invention provides a system for providing tunable balanced loss compensation in an electronic filter. Tunable balanced loss compensation is provided by using cross-connected balanced transconductors and self-connected balanced transconductors. The cross-connected balanced transconductors and the self-connected transconductors compensate the unbalanced loss across the electronic filter. The self-connected balanced transconductors compensate the balanced loss across the electronic filter. Further, the cross-connected and the self-connected balanced transconductors are tunable by adjusting the values of their transconductances, thereby providing tunable balanced loss compensation.

Abstract: A circuit and method for tracking a local oscillator signal frequency in an RF tuner, for tuning input RF signals. The RF tuner includes a frequency-dependent impedance generator that generates a frequency-dependent impedance at the input by rejecting unwanted input RF signals and shunt feeding back the desired signal to the input. The desired signal frequency is centered at the local oscillator signal frequency. The frequency-dependent impedance generator is used with an amplifier circuit to generate a tracking amplifier, the frequency-dependent amplifier gain of which tracks the local oscillator signal frequency.

Abstract: The invention provides a system for providing tunable balanced loss compensation in an electronic filter. Tunable balanced loss compensation is provided by using cross-connected balanced transconductors and self-connected balanced transconductors. The cross-connected balanced transconductors and the self-connected transconductors compensate the unbalanced loss across the electronic filter. The self-connected balanced transconductors compensate the balanced loss across the electronic filter. Further, the cross-connected and the self-connected balanced transconductors are tunable by adjusting the values of their transconductances, thereby providing tunable balanced loss compensation.

Abstract: The invention provides a system and method for tuning broadband signals by using post mixer I/Q equalization. An Image Rejection Mixer (IRM) is used for mixing Radio Frequency (RF) signals and rejecting image signals from the desired RF signals. The IRM includes an I/Q mixer and a filter. The I and Q paths resulting from the mixing operation in the I/Q mixer are equalized in amplitude and phase by an I/Q equalizer. Thereafter, the image signals are rejected from the desired RF signals using the filter.

Abstract: A single-input/multiple output power splitter having internal feedback circuitry. A separate amplifying circuit, such as a transistor, is used to drive each of the outputs. The transistors may be arranged in a common source/emitter amplifying configuration in which the gates/bases are connected together as an input node. Each transistor has an associated feedback circuit including passive circuit elements, such as resistors. The passive circuit elements are connected between the drain/collector of its corresponding transistor and a common intermediate connecting node to which all feedback resistors are also connected. The common intermediate node is connected to the single input via a separate input resistor.

Abstract: A multiple-frequency local oscillator for providing an LO signal at one of a multiple of predetermined resonant frequencies associated with a number of resonators is disclosed. It includes a number of LO input ports for coupling to a plurality of resonators, respectively, each resonator having a predetermined resonant frequency; the local oscillator is controlled to selectively provide at its LO output port an output LO signal at any one of the resonant frequencies.