A receiver includes one or more mixers configured to sample an input analog signal at a plurality of discrete points in time to obtain a discrete-time sampled signal based on a local oscillating signal provided by a local oscillator; and a sample reordering circuit coupled to the one or more mixers and configured to reorder a sequence of samples received from the one or more mixers.

A circuit comprising a differential transmission line and eight switches provides non-reciprocal signal flow. In some embodiments, the circuit can be driven by four local oscillator signals. The circuit can be used to form a gyrator. The circuit can be used to form a circulator. The circuit can be used to form three-port circulator than can provide direction signal flow between a transmitter and an antenna and from the antenna to a receiver. The three-port circulator can be used to implement a full duplex transceiver that uses a single antenna for transmitting and receiving.

The disclosure relates to technology for shifting a frequency range of a signal. In one aspect, a circuit comprises a frequency mixer, a frequency synthesizer configured to generate an oscillator signal, a programmable driver, and a controller. The programmable driver is configured to receive the oscillator signal from the frequency synthesizer and to provide the oscillator signal to the oscillator input of the frequency mixer. The programmable driver is configured to have a variable drive strength. The controller is configured to control the drive strength of the programmable driver based on a frequency of the oscillator signal to adjust a rise time and a fall time of the oscillator signal at the oscillator input of the frequency mixer.

A phase adjustment circuit includes: a local frequency band phase shifter that adjusts a phase of a signal in a local signal frequency band and that outputs the adjusted signal; a frequency-converting mixer that receives the adjusted signal and another signal different from the adjusted signal, and that mixes the adjusted signal with the other signal; and a buffer amplifier that is provided between the local frequency band phase shifter and the frequency-converting mixer, and that is capable of amplifying an input power that is to be input to the frequency-converting mixer so that the input power is up to be in an input power range in which an input-output characteristic of power of the frequency-converting mixer is out of a linear region.

A method for initializing a phase adder circuit including a multiplier circuit with its two inputs receiving signals of frequency f.sub.o, a mixer circuit, an amplifier circuit, a low pass loop filter, and a voltage controlled oscillator (VCO), the method including: during a first phase, determining a reference voltage which when applied to the VCO causes it to produce a signal having a frequency of nf.sub.0; during a second phase, supplying a signal of frequency nf.sub.o to a first input of the mixer and a signal of frequency (nf.sub.o+Δf) to a second input of the mixer; and determining an adjustment signal which when applied to the amplifier circuit causes the amplifier circuit to output a signal having a DC component equal to the reference voltage; and during a third phase, forming a primary phase locked loop (PLL) circuit including the mixer, the amplifier circuit, the low pass loop filter and the VCO; and applying the adjustment signal to the amplifier circuit.

A mixer includes a load portion connected between an input terminal of a first power voltage and an output terminal of the radio frequency transmit signal and configured to adjust a magnitude of the radio frequency transmit signal, a first switching unit connected to an output terminal of the radio frequency transmit signal, and configured to perform a first switching operation in response to a plurality of local oscillation signals, and a second switching unit connected between the first switching unit and an input terminal of a second power voltage, lower than the first power voltage, and configured to perform a second switching operation in response to a plurality of baseband signals, the plurality of local oscillation signals include an I+ baseband signal, an I baseband signal, a Q+ baseband signal, and a Q baseband signal, and the second switching unit includes a first branch performing a switching operation under control of the I+ baseband signal and the Q+ baseband signal, a second branch performing a switching operation under control of the I baseband signal and the Q baseband signal, a third branch performing a switching operation under control of the Q+ baseband signal and the I baseband signal, and a fourth branch performing a switching operation under control of the Q baseband signal and the I+ baseband signal.

Radio frequency (RF) mixer circuits having a complementary frequency multiplier module that requires no balun to multiply a lower frequency base oscillator signal to a higher frequency local oscillator (LO) signal, and which has a significantly reduced IC area compared to balun-based frequency multipliers. In one embodiment, the complementary frequency multiplier module includes a complementary pair of FETs controlled by an applied base oscillator signal. The complementary FETs are coupled to a common-gate FET amplifier and alternate becoming conductive in response to the base oscillator signal. The alternating switching of the complementary FETs in response to the opposing phases of the base oscillator signal cause the common-gate FET amplifier to output a higher frequency local oscillator (LO) signal. The LO signal is coupled to the LO input of a mixer or mixer core of a type suitable for use in conjunction with a frequency multiplier.

A dual-band mixer circuit includes a mixer configured to receive an input signal and a local oscillator (LO) signal and to generate an output frequency signal, and a switchable inductance circuit coupled to an output of the mixer, and including a transformer including a primary inductor and a secondary inductor, the primary inductor being electrically coupled to the output of the mixer, a capacitor electrically coupled to the secondary inductor, and a switch electrically coupled to the capacitor and the secondary inductor.

Techniques are provided for decorrelation of intermodulation products in mixer circuits. A circuit implementing the techniques according to an embodiment includes four switches. Each of the switches comprise a complementary pair of n-channel and p-channel metal oxide semiconductor (NMOS/PMOS) field effect transistors (FETs). The NMOS/PMOS FETs include a source port, a drain port, and a gate port. The gate port is configured to receive an oscillator signal. The circuit also includes electrical conductors to couple the four switches into a double-balanced passive ring configuration to generate an output signal as a mix of an input signal and the oscillator signal. The output signal includes a third order intermodulation (IM3) product. The circuit further includes a voltage bias generator to generate a bias voltage to bias the input signal and the output signal. The magnitude and phase of the IM3 product are determined, at least in part, by the bias voltage.

A double-balanced radio-frequency (RF) mixing digital-to-analog converter (DAC) apparatus includes a load network, a first set of resistive DAC driver circuits and a first mixing core. The first mixing core can receive first RF input signals from the first set of resistive DAC driver circuits and can provide a first mixed signal to the load network. The first mixing core includes a first input differential pair coupled to two first cross-coupled differential pairs. The first input differential pair can receive first RF input signals at respective first input nodes. Each of the two first cross-coupled differential pairs can receive first positive and negative local oscillator (LO) signals at corresponding first input nodes. The first mixing core can mix the first RF input signals with the first positive and negative LO signals.