186 results about "Harmonic mixer" patented technology

Receiver architectures and methods of processing harmonic rich input signals employing harmonic suppression mixers are disclosed herein. The disclosed receivers, mixers, and methods enable a receiver to achieve the advantages of switching mixers while greatly reducing the mixer response to the undesired harmonics. A harmonic mixer can include a plurality of mixers coupled to an input signal. A plurality of phases of a local oscillator signal can be generated from a single local oscillator output. Each of the phases can be used to drive an input of one of the mixers. The mixer outputs can be combined to generate a frequency converted output that has harmonic rejection.

The invention provides a power calibration test system. The power calibration test system comprises a system setting device for setting target power and a target frequency band, a power meter connected with the system setting device and used for measuring output power in cooperation with a power sensor, a microwave vector network analyzer connected with the power meter and used for generating microwave signals, a frequency multiplier connected with the microwave vector network analyzer, a three-port directional coupler connected with the frequency multiplier, and a harmonic mixer connected with the microwave vector network analyzer and the three-port directional coupler. By means of a closed loop feedback loop, real-time closed loop monitoring and adjustment on input power of the reference plane of an input port of a component to be tested are achieved, real-time closed loop calibration on power within any frequency band and accurate measurement on circuits and devices can be achieved, and the universality, effectiveness, consistency and accuracy of the power calibration test system are largely improved.

A method and apparatus for frequency down-converting a radio frequency (RF) signal to baseband in two steps using the two quadrature components of a single local oscillator. In the first stage, the RF signal is mixed with both components of the local oscillator signal (LO) in a sub-harmonic mixer to produce an intermediate frequency (IF) output signal having a frequency component at twice the local oscillator frequency minus the RF frequency, i.e., (2×LO)−RF=IF. In the second stage, the IF signal is split into two and supplied to a quadrature mixer that mixes the IF signal with the I component of the same local oscillator signal and separately mixes the IF signal with the Q component of the same local oscillator signal to produce an output signal comprising an I component and a separate Q component at baseband.

A single chip GSM/EDGE transceiver comprises a fully differential receive chain, a subharmonic mixer in the receive chain, the subharmonic mixer configured to receive a radio frequency (RF) input signal and a local oscillator (LO) signal that is phase-shifted by a nominal 45 degrees, and a synthesizer having a voltage controlled oscillator and having at least one frequency divider to generate desired transmit and receive LO signals. The transceiver also comprises a transmitter having a closed power control loop, and a harmonic rejection modulator, the use thereof made possible by a frequency plan designed to allow the synthesizer to develop the transmit and receive LO signals without a frequency multiplier.

The invention discloses a monolithic integration technology based terahertz frequency mixing circuit. The monolithic integration technology based terahertz frequency mixing circuit comprises a radio frequency 3dB branch waveguide directional coupler, a local oscillation 135-degree phase shift 3dB branch waveguide directional coupler, a coaxial probe, an intermediate coupling ring, an intermediate frequency signal and two terahertz sub-harmonic mixers; each terahertz sub-harmonic mixer comprises radio frequency waveguide-microstrip transition, a monolithic integration Schottky diode pair, a local oscillation waveguide-microstrip transition, an intermediate frequency filter and a local oscillation low-pass filter; and the monolithic integration Schottky diode pair is a diode pair in inverse parallel connection. The harmonic mixers in the erahertz frequency mixing circuit are obtained by adopting a semiconductor technology; the position of diodes and the size of a micro-strip circuit can be controlled precisely; the error is far less than that of manual configuration; the influence from the configuration error to the performance of the frequency mixing circuit is reduced greatly; meanwhile, the frequency mixing circuit can remove local oscillation noise efficiently and improves the noise performance and the efficiency of a system.

A 3-terminal harmonic mixer which solves the conversion gain, port impedance and isolation problems associated with known harmonic mixers. In particular, the 3-terminal harmonic mixer in accordance with the present invention provides harmonically pumped anti-parallel diode mixing operation by utilizing the inherent characteristics of complementary transistors.

A mixer design is described that permits greater integration on standard silicon chips with an improvement in power and linearity compared to previous mixer designs, enabling low-power, high performance RF reception.

Provided is a sub-harmonic frequency mixer having a structure in which two terminals of transistors receiving a Radio Frequency (RF) signal and a Local Oscillation (LO) signal are coupled. The frequency mixer is composed of a single-level structure of transistors and thus can be driven at a lower supply voltage compared to a common frequency mixer. A direct-conversion receiver employing such a frequency mixer needs an RF signal and an LO signal sources of single-phase. Therefore, the direct-conversion receiver has an architecture that simplifies a whole RF transceiver circuit and thus can be advantageously applied in implementing SoC (System-on-Chip) for a low power, high integration, low price and subminiature wireless transceiver circuit.

A wide band mixer is provided that mitigates local oscillator leakage. A LO signal is provided to a 180 degree splitter that provides a first intermediate LO signal and a second intermediate LO signal 180° out of phase from one another. Since both the first and second intermediate LO signals are 180° out of phase, the fundamental LO leakage is mitigated at the RF port by the in-phase combination of the 180° out of phase LO tones canceling one another out and providing strong LO/RF rejection. An RF or microwave input signal is provided to a power splitter to provide a first intermediate RF signal and a second intermediate RF signal. The first intermediate LO signal is mixed with the first intermediate RF signal and the second intermediate LO signal is mixed with the second intermediate RF signal to provide an intermediate frequency signal at the output of the mixer.

A quadrature subharmonic mixer comprises a polyphase filter configured to generate quadrature components of a local oscillator (LO) reference signal, a summing and scaling element configured to create additional components of the LO reference signal, and a plurality of mixer elements configured to multiply the quadrature components of the LO reference signal and the additional components of the LO reference signal with a radio frequency (RF) signal to obtain a downconverted version of the RF signal.

The invention discloses a method for measuring electric energy of a harmonic power network. The method comprises the following steps of: collecting harmonic content and harmonic waves injected in the power network by a user; calculating the total harmonic distortion (THD) of harmonic waveforms at different time intervals, judging a relationship between the THD and a preset waveform distortion factor threshold value, and respectively calculating the electric energy in different measuring modes. A threshold value (referring to a national harmonic standard limit) is set according to different THDs under harmonic conditions so as to distinguish that the user is a harmonic user or a non-harmonic user in different measuring modes, if the harmonic influence is large, and the user serves as a linear user, the sum of electric energy of the consumed fundamental waves and harmonic waves is calculated, and simultaneously the electric energy of the harmonic waves injected into the power network is recorded so as to be used as a technical reference index; and if the harmonic influence is extremely large and belongs to a typical harmonic source load, the sum of absolute values of the electric energy of the consumed fundamental waves and harmonic waves and the harmonic waves injected into the power network is calculated, and an aim of controlling the harmonic waves is fulfilled finally.

A sub-harmonic mixer includes a first transistor having a source and a drain and a second transistor having a source connected to the source of the first transistor and a drain connected to the drain of the first transistor. A mixing transistor is configured to be biased in a linear operating region. The mixing transistor includes a drain coupled to the sources of the first transistor and the second transistor. The mixing transistor has its drain driven by a signal at twice a local oscillator (LO) frequency and its gate driven by a radio frequency (RF) signal while the mixing transistor is biased in the linear region such that a process of frequency doubling and mixing are performed simultaneously.

The invention provides a 340GHz eighth harmonic mixer. The 340GHz eighth harmonic mixer comprises a radio-frequency input waveguide, a radio-frequency waveguide-suspended microstrip transition structure, a diode, a radio-frequency suppressing low-pass filter, a suspended microstrip-microstrip interconnecting structure, an intermediate-frequency filter, a local oscillator waveguide-microstrip transition structure and a local oscillator input waveguide; a radio-frequency signal is input from the radio-frequency input waveguide and coupled and fed into the diode via the radio-frequency waveguide-suspended microstrip transition structure; the intermediate-frequency filter, the local oscillator waveguide-microstrip transition structure and the local oscillator input waveguide are combined to form a local oscillator-intermediate-frequency duplexer; a local oscillator is fed into the diode after orderly passing through the duplexer, the suspended microstrip-microstrip interconnecting structure and the radio-frequency suppressing low-pass filter; the radio-frequency signal and the local oscillator signal are mixed in the diode and a mixed signal is output. According to the 340GHz eighth harmonic mixer, an eighth harmonic mixing form is adopted so that the local frequency is greatly reduced; meanwhile, the size of the mixer is effectively reduced and the manufacturing difficulty and cost are reduced.

The invention discloses a millimeter-wave even harmonic mixer structure. The millimeter-wave even harmonic mixer structure comprises a frequency-mixing microstrip chip, an antiparallel diode pair, a local-oscillator low-pass filter and an intermediate-frequency low-pass filter, wherein the frequency-mixing microstrip chip is disposed in a radio-frequency waveguide in a direction identical with the waveguide and is disposed in the center of a broadside of the radio-frequency waveguide, the antiparallel diode pair is disposed at the tail end of the frequency-mixing microstrip chip, and the local-oscillator low-pass filter and the intermediate-frequency low-pass filter are arranged on the end face of the tail end of the radio-frequency waveguide, determine the length of the frequency-mixing microstrip chip disposed in the radio-frequency waveguide according to local oscillator signals and determine the width of a grounding end of the frequency-mixing microstrip chip according to the size of the antiparallel diode pair. The millimeter-wave even harmonic mixer structure has the advantages that radio-frequency signals can be well coupled to diodes, and when radio-frequency signals and the local oscillator signals are subjected to frequency mixing, the millimeter-wave even harmonic mixer structure is excellent in frequency conversion performance, high in consistency and broader in operation bandwidth.

A microwave and millimetric wave quartic frequency mixer is composed of a stopping direct coupler, two stage microstrip oper wires, a schottky reverse diode pair, two stage compact microphand resonance units, two microband high-low impedance line low pass filter. Since the used local frequency is 1/4 of the basic wave frequency mixer, its performance is increased greatly, and the compact microband resonance unit can either transfer the local signal and provide RF signal circuit or flexible adjust the idle terminal reactivity load, so as to suppress the idle frequency to reduce frequency conversion loss.

A method and apparatus for frequency up-converting a baseband signal to radio frequency (RF) in two steps using the two quadrature components of a single local oscillator signal. In a first stage, the baseband signal is split into two parts in quadrature with each other and supplied to a quadrature mixer that mixes the one component of the baseband signal with the I component of a local oscillator signal at frequency F_LO and separately mixes the other baseband component with the Q component of the same local oscillator to produce an intermediate frequency signal centered at the local oscillator frequency and comprising two components, namely, an I component and a Q component. In the second stage, the intermediate frequency signal is mixed with both components of the same local oscillator signal in a sub-harmonic mixer-to produce a radio frequency output signal having a frequency component at three times the local oscillator frequency minus the baseband frequency.

The invention provides a novel terahertz band broadband monolithic integrated subharmonic mixer comprising radio frequency and a local oscillation signal loading coupler, a diode pair composed of two diodes reversely connected in parallel, an intermediate frequency output amplifier circuit and a low pass filter, wherein a radio frequency signal is filtered by a first coplanar waveguide through a radio frequency band stop filter with a 1/2 radio frequency signal wavelength and is imported by a second coplanar waveguide onto an intermediate pin of the diode pair; and a local oscillation signal is filtered by a third coplanar waveguide through a local oscillation band-pass filter with a 1/4 local oscillation signal wavelength and is imported by the second coplanar waveguide onto the intermediate pin of the diode pair to be mixed with the radio frequency signal. By adoption of the scheme, the ultra wide working frequency range of the terahertz monolithic integrated subharmonic mixer is realized, and the scheme has the performance indexes of low frequency conversion loss, low manufacturing cost and high port isolation, and the like.

A mixer converts input power at high-frequency RF into output power at a different and much lower frequency IF, with the assistance of another high-frequency oscillator (LO). Typically, a very low IF frequency requires an LO that approximates the RF frequency. However, a subharmonic mixer facilitates low IF with LO frequencies significantly lower than the RF frequency. This balanced odd-subharmonic mixer consists primarily of a four-port BALUN and a pair of diodes. The diodes terminate two ports of the BALUN connecting in series and in anti-parallel to the remaining external BALUN ports. The external BALUN ports constitute the RF and the LO high-frequency mixer ports. The mixer's lower-frequency IF port also connects to the diodes, comprising a separate channel that is co-linear with one BALUN external port, and coupling capacitively to the other. All three mixer ports meet at a mixing chamber (part of the BALUN) where the diodes are located.