An access point includes a WiFi chipset, a first radio that is coupled to the WiFi chipset and that is selectively coupled to a first radiating element through one of a first filter or a second filter, and a second radio that is coupled between the WiFi chipset and a second radiating element.

Certain disclosed embodiments pertain to suppressing interference in a wireless communication system. For example, a method of suppressing interference can include receiving one, two, or more first signals including components from a plurality of sub-channels. Each of the first signals can be processed by a Finite Impulse Response filter adapted using an LMS update algorithm,

A wireless single-phase AC-to-AC conversion circuit based on a 2.4G microwave includes a receiving antenna unit, a RF switch unit, a positive voltage rectification unit, a negative voltage rectification unit and an AC synthesis unit. An output port of the receiving antenna unit is connected to the common input port of the RF switch unit. A first microwave output end of the RF switch unit and a second microwave output end of the RF switch unit are correspondingly connected to a microwave input end of the positive voltage rectification unit and a microwave input end of the negative voltage rectification unit, respectively. ADC output end of the positive voltage rectification unit and a DC output end of the negative voltage rectification unit are correspondingly connected to a positive voltage input port of the AC synthesis unit and a negative voltage input port of the AC synthesis unit, respectively.

A transceiver disposed on a first die in a bidirectional differential die-to-die communication system is disclosed. The transceiver includes a transmission section configured to modulate a first data onto a carrier signal having a first frequency for transmission via a bidirectional differential transmission line; and a reception section configured to receive signals from the bidirectional differential transmission line, the reception section including a filter configured to pass frequencies within a first passband that includes a second frequency, the first frequency being outside of the first passband. According to some embodiments, the reception section is configured to receive, via the bidirectional differential transmission line, modulated data at the second frequency at a same time that the transmission section transmits the modulated data at the first frequency.

An architecture can include a first group of filters each configured to support a band such that a first frequency range covers the respective bands, and a second group of one or more filters each configured to support a band such that a second frequency range covers the respective one or more bands. Each filter of the first group can be configured to provide an impedance at or near a short circuit impedance for a signal in each band of the second group, and each filter of the second group can be configured to provide an impedance at or near a short circuit impedance for a signal in each band of the first group. The filters of the first and second groups can be implemented as one or more multiplexers. The architecture can further include a coupling circuit having a common node and configured to couple the common node to the one or more multiplexers through a first path and a second path. The coupling circuit can be further configured such that the impedance provided by each filter of the first group for the signal in each band of the second group results in the signal being sufficiently excluded from the first path, and such that the impedance provided by each filter of the second group for the signal in each band of the first group results in the signal being sufficiently excluded from the second path.

This disclosure provide various techniques for improving the quality of a signal. By integrating phase-shifting circuitry with a transmit/receive (T/R) switch, insertion loss may be reduced while decreasing space consumed on an integrated circuit or printed circuit board. In particular, embodiments disclosed herein include a transmitter and a receiver, each including one or more differential amplifiers coupled to a first inductor, and a switching network coupled to a second inductor and one or more phase-shifting circuitries. A differential interface of the differential amplifiers may enable integration of a stage of the phase shifter (e.g., a 180 degree stage) with the T/R switch, such that a single circuit may operate as the phase shifter and the T/R switch. This implementation may reduce the number of T/R switches and phase shifter stages in the phased array system, reducing the overall insertion loss experienced by the phased array system.

Equalization filter calibration in a wideband transmission circuit is provided. The transceiver circuit generates a radio frequency (RF) signal(s) from a time-variant modulation vector and a power amplifier circuit(s) amplifies the RF signal(s) based on a modulated voltage. The transceiver circuit is configured to apply an equalization filter to the time-variant modulation vector to thereby compensate for a voltage distortion filter created at the output stage of the power amplifier circuit(s). In embodiments disclosed herein, a calibration circuit can be configured to calibrate the equalization filter across multiple frequencies within a modulation bandwidth of the power amplifier circuit to generate a gain offset lookup table (LUT) and a delay LUT. As a result, the equalization filter can be dynamically adapted to reduce undesired instantaneous excessive compression and/or spectrum regrowth resulting from the voltage distortion filter across the modulation bandwidth of the power amplifier circuit.

Radio frequency switches with improved switching speed are provided. In certain embodiments, an RF switching circuit includes a FET switch including a gate, a digital buffer configured to provide a first output voltage to the gate of the FET during a steady-state, and a fast switching circuit in parallel with the digital buffer and configured to provide a second output voltage to the gate of the FET during a switching state. The fast switching circuit includes at least one charge pump configured to boost at least one supply voltage to a multiple of the at least one supply voltage. The fast switching circuit is configured to generate the second output voltage based on the boosted at least one supply voltage.

Apparatus and methods for envelope controlled radio frequency (RF) switches are provided. In certain embodiments, a power amplifier provides an RF signal to an antenna by way of an RF switch. Additionally, the envelope signal is used not only to control a power amplifier supply voltage of the power amplifier, but also to control a regulated voltage used to turn on the RF switch. For example, a level shifter can use a regulated voltage from charge pump circuitry to turn on the RF switch, and the envelope signal can be provided to the charge pump circuitry and used to control the voltage level of the regulated voltage over time.

The radio frequency front-end systems herein include modules having bandwidth controllable components, such as amplifier and filters. By implementing the modules with bandwidth control, the same module can be used for operation of multiple frequency bands including a first frequency band and a second frequency band. Thus, when implementing features such as carrier aggregation, multiple-input multiple-output (MIMO), and/or sounding resource signaling (SRS) for supporting the multiple frequency bands, the total number of modules used can be reduced and/or additional feature support can be provided compared to an implementation in which each module supports a single frequency band.