A method for detecting a beacon signal using an above-ground tracker. The tracker comprises an antenna assembly comprising a plurality of antennas. Each antenna is oriented in a different direction. During operation, if the beacon signal is interrupted due to a local noise source, transmission of the beacon signal is stopped. The tracker then detects radiation from the local noise source and the processor determines a direction from which peak ambient noise arrives at the tracker. The beacon signal is then resumed. A processor included in the tracker excludes any signals generated by the antenna assembly that are representative of radiation that arrived at the tracker from the same direction the peak ambient noise arrived at the tracker. The tracker then detects the beacon signal using the non-excluded signals.

On-chip Multi-band equalizers for adjusting signal strength for a receiver receiving multi-band frequency signals are provided, The multi-band equalizer comprises multiple series connected tapped LC resonators. The tapped LC resonator may be capacitive tapping or inductive tapping, where both frequency and gain of the frequency bands of interest may be programmed by tuning the capacitances of the programmable capacitors and/or selecting the tapped out terminals of the inductors. The multi-band equalizer may be connected to a signal node, for instance between two amplifiers in the receiver.

An antenna system includes: a radiating element; a feed coupled to the radiating element at a first point on the radiating element and configured to convey energy to the radiating element; and a radiation-adjustment device coupled to the radiating element at a second point, configured to alter a radiation characteristic of the radiating element, and including: coarse-adjustment elements; an integrated-circuit chip including: switches, each coupled to a respective one of the coarse-adjustment elements where the coarse-adjustment elements are disposed external to the integrated-circuit chip; and a fine-adjustment circuit; the antenna system further including a controller communicatively coupled to the switches and to the fine-adjustment circuit, the controller configured to alter the radiation characteristic of the radiating element by selectively causing one or more of the switches to couple one or more of the coarse-adjustment elements to the radiating element, and by adjusting a value of the fine-adjustment circuit.

An electronic device may include wireless circuitry with a baseband processor, a transceiver, and an antenna. The transceiver may include a mixer that outputs signals to a transimpedance amplifier. The mixer has an output impedance that varies depending on the frequency of operation. An adjustable resistance can be coupled to the input of the transimpedance amplifier. A control circuit can tune the adjustable resistance to compensate for changes in the output impedance of the mixer as the transceiver operates across a wide range of frequencies.

Frequency ranges may be converted by an apparatus including a converter configured to shift an original frequency range of an input data signal to a target frequency range, an input band selective filter bank configured to route the input data signal through a bandpass filter of a selected subrange within the target frequency range, the input selective filter bank including a plurality of bandpass filters, each bandpass filter having a corresponding subrange within the target frequency range.

An electronic device may include wireless circuitry with a baseband processor, a transceiver, and an antenna. The transceiver may include a mixer that outputs signals to a transimpedance amplifier. The mixer has an output impedance that varies depending on the frequency of operation. An adjustable resistance can be coupled to the input of the transimpedance amplifier. A control circuit can tune the adjustable resistance to compensate for changes in the output impedance of the mixer as the transceiver operates across a wide range of frequencies.

Embodiments of this disclosure may include a receiver with a reconfigurable processing path for different signal conditions. Such a receiver may reconfigure between a mixer-first configuration and an amplifier-first configuration. In the mixer-first configuration, an RF input signal is not passed through an LNA for amplification before processing the RF input signal for downconversion to baseband and eventual extraction of the information in the signal. In the amplifier-first configuration, an RF input signal is passed through an LNA for amplification before processing the RF input signal for downconversion to baseband and eventual extraction of the information in the signal. Reconfiguring the receiver between mixer-first and amplifier-first configurations may be performed based on detection of jammer signals and/or measurement of signal-to-noise ratio (SNR).

Front-end circuitry is difficult to design for high sample rate, wide bandwidth receivers with high performance requirements on noise and linearity. One exemplary front-end circuitry is integrated on-chip with the RF ADC in a receiver, and the circuitry implements ESD protection, attenuation, and gain. The circuitry includes a multi-tap filter with LC circuits, and the filter implements a highly linear filter. Advantageously, the capacitors in the LC circuits are also used for ESD protection. Additionally, tunable attenuator cells are implemented across the multi-tap filter to provide a wide range of variable attenuation. The circuitry can further include a fixed or variable gain stage at the output. The resulting circuitry offers variable gain and attenuation while meeting bandwidth, noise, and linearity requirements.

A user equipment, method and computer program for adjusting an effective centre frequency of channel filter in a user equipment to improve the adjacent selectivity when the network is transmitting on an irregular bandwidth channel and the user equipment is receiving the signal via a channel filter that has a wider pass band than the bandwidth of the channel. The method comprises filtering received wireless communication signals at a channel filter. Identifying a preferred centre frequency for the channel filter by: adjusting a centre frequency of the channel filter; determining a level of adjacent channel selectivity of signals filtered by the channel filter; comparing a level of adjacent channel selectivity at different centre frequencies of the channel filter; and identifying the preferred centre frequency as the centre frequency that provides a highest level of adjacent channel selectivity.

A method for tuning an analog front end response is provided. The method includes determining a peaking control value for an analog front end (AFE) of a receiver, determining an attribute corresponding to the peaking control value, selecting the peaking control value as the operating peaking control value for the AFE based on the attribute being determined to be higher than a previous attribute, and performing a receiver adaptation using the peaking control for a one or more transmitter configurations.