Patent classifications
H03D7/125
SYSTEMS AND METHODS FOR DETECTING LOCAL OSCILLATOR LEAKAGE AND IMAGE TONE IN I/Q MIXER BASED TRANSCEIVERS
A detector circuit includes: a squaring circuit configured to receive an output of a power amplifier of a radio transmitter and to produce an output current, the output of the power amplifier including: a desired tone; a local oscillator leakage tone; and an image tone, and the output current of the squaring circuit including: a direct current (DC) component including a function of the desired tone and an alternating current (AC) component; and a DC current absorber electrically connected to an output terminal of the squaring circuit, the DC current absorber being configured to filter out the DC component of the output current of the squaring circuit to produce a filtered output of the squaring circuit, the filtered output including the AC component including functions of the local oscillator leakage tone and the image tone.
Discrete time superheterodyne mixer
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.
Swing tracking and control
In certain aspects, an apparatus includes a transformer including an input inductor and an output inductor, wherein the input inductor is magnetically coupled to the output inductor. The apparatus also includes a transconductance driver configured to drive the input inductor based on an input signal. The apparatus further includes a feedback circuit configured to detect an output voltage swing at the output inductor, generate a regulated voltage at the input inductor, and control the regulated voltage based on the detected output voltage swing.
Source Injection Mixer
A source injection mixer includes an FET, an IF matching circuit between an IF port and a gate of the FET, and that matches impedance of the IF port and impedance of the gate as viewed from the IF port, a shorting stub of which one end is connected to a source of the FET and another end is grounded, and shorter than ¼ of an electric length at a frequency of LO signals, an LO matching circuit between an LO port and the source of the FET, and that matches impedance of the LO port and impedance of the source as viewed from the LO port, and an RF matching circuit between an RF port and a drain of the FET, and that matches impedance of the RF port and impedance of the drain as viewed from the RF port.
DECORRELATION OF INTERMODULATION PRODUCTS IN MIXER CIRCUITS
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.
SPLIT MIXER CURRENT CONVEYER
The disclosure relates to technology for an apparatus having a current conveyer comprising a first stage having a first differential input, and a second stage having a second differential input. The first and second stages are configured to operate in a push-pull mode to provide an output signal at a current conveyer output between the first stage and the second stage. The apparatus has a first frequency mixer configured to generate a first mixer signal based on an input signal and an oscillator signal having a first frequency. The first frequency mixer is configured to provide the first mixer signal to the first differential input. The apparatus has a second frequency mixer configured to generate a second mixer signal based on the input signal and a second oscillator signal having the first frequency. The second frequency mixer is configured to provide the second mixer signal to the second differential input.
DISCRETE TIME SUPERHETERODYNE MIXER
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.
Mixer circuit
The invention relates to a mixer circuit, which includes a transconductance stage circuit, a switch stage circuit and a load stage circuit which are electrically connected in sequence. The transconductance stage circuit is used to access a radio frequency voltage signal and convert the radio frequency voltage signal into a radio frequency current signal The switch-level circuit is used to access the local oscillator signal and the radio frequency current signal, and the switch-level transistor is turned on by using the local oscillator signal; the load-level circuit is used to convert the intermediate frequency current signal into a voltage signal for output. In the present invention, the transconductance stage circuit adopts a transistor superposition technology structure, which improves the conversion gain of the mixer; at the same time, it uses a source degenerate inductance structure, which further improves the conversion gain and linearity of the circuit.
Discrete time superheterodyne mixer
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.
Systems and methods for detecting local oscillator leakage and image tone in I/Q mixer based transceivers
A detector circuit includes: a squaring circuit configured to receive an output of a power amplifier of a radio transmitter and to produce an output current, the output of the power amplifier including: a desired tone; a local oscillator leakage tone; and an image tone, and the output current of the squaring circuit including: a direct current (DC) component including a function of the desired tone and an alternating current (AC) component; and a DC current absorber electrically connected to an output terminal of the squaring circuit, the DC current absorber being configured to filter out the DC component of the output current of the squaring circuit to produce a filtered output of the squaring circuit, the filtered output including the AC component including functions of the local oscillator leakage tone and the image tone.