摘要:
A quadrature phase clock generator includes a tunable polyphase filter and a phase detector. The tunable polyphase filter is configured to receive an input clock signal and generate four quadrature phase clock signals. The phase detector is coupled to receive at least two of the four quadrature phase clock signals and generate a control signal adapted to tune the polyphase filter based on the received quadrature phase clock signals. Further, the phase detector is configured to provide the control signal to the polyphase filter in a feedback loop. Based on the control signal from the phase detector, the tunable polyphase filter generates four tuned quadrature phase clock signals as output phase clock signals.
摘要:
A radio-frequency switching apparatus that can be used to turn a signal path on or off or to attenuate a radio-frequency signal. The switching apparatus comprises at least one radio-frequency input, at least one radio-frequency output, at least one transmission line providing a signal path between the at least one radio-frequency input and the at least one radio-frequency output, and at least one transition metal oxide portion. The radio-frequency switching apparatus also comprises direct current blocking means electrically coupled between the at least one transition metal portion and the at least one radio-frequency input. The radio-frequency switching apparatus also comprises biasing means for providing a bias across the at least one transition metal oxide portion such that power transferred between the radio-frequency input and the radio-frequency output is controlled by controlling the bias level across the at least one transition metal oxide portion.
摘要:
A first input terminal is connected to a point of connection of a drain terminal of a first transistor and a gate terminal of a fourth transistor. A second input terminal is connected to a point of connection of a drain terminal of a third transistor and a gate terminal of a second transistor. One of first through fourth output terminals to is connected to a source terminal of each of the first through fourth transistors to. A gate terminal of the first transistor and a drain terminal of the second transistor are connected, and a gate terminal of the third transistor and a drain terminal of the fourth transistor are connected.
摘要:
Described herein are systems and methods that allow for correcting a residual frequency offset in the GHz frequency range by using low-complexity analog circuit implementations of a broad-band frequency detector that comprises two analog polyphase filters in a dual configuration. Each filter comprises an RC network of cross-coupled capacitors that facilitate filters with opposite passbands and opposite stop-bands. In various embodiments, the outputs of the two filters are combined to obtain power metrics that when subtracted from each other, deliver a measure of the imbalance between the positive and negative halves of a frequency spectrum. Since the measure is substantially proportional to a frequency offset within a linear range spanning 5 GHz or more, the polyphase filters may be used in a broad-band frequency detector that, based on the measure, adjusts the frequency offset.
摘要:
A passive phase shifter includes a reference line and a half-wavelength transmission line, where the half-wavelength transmission line is loaded with a perpendicular quarter wavelength rectangular stub and a quarter wavelength radial stub structure connected in series.
摘要:
A method for in-phase (I) and quadrature (Q) signal generation is disclosed. The method may include a first stage receiving a differential input signal. The first stage may also generate first differential in-phase and quadrature output signals, which may be sent by the first stage to a second stage. The second stage may generate second differential in-phase and quadrature output signals, which may have amplitude and phase mismatches less than an amplitude and phase mismatches of the first differential output signals. The second stage may then output the second differential I/Q output signals.
摘要:
Apparatuses and methods for quadrature signal generation are provided. An example includes a quadrature signal generator. The quadrature signal generator is configured to generate, based on a received differential signal, a plurality of quadrature clock signals at a same frequency as that of the received differential signal. The quadrature signal generator is also configured to provide the plurality of quadrature clock signals to a memory system.
摘要:
The present invention discloses an ultra wide band fixed phase shifter based on a capacitive load, which includes N physically separated phase shift units, and each phase shift unit includes an orthocoupler, first and second transmission lines, and first and second capacitive loads, wherein the orthocoupler includes an input end, a coupling end, a direct-connection end and an isolation end, one end of the first transmission line serves as a signal input end of the phase shift unit and the other end is connected with the input end of the orthocoupler, one end of the second transmission line serves as a signal output end of the phase shift unit and the other end is connected with the isolation end of the orthocoupler; one end of the first capacitive load is connected with the coupling end of the orthocoupler and the other end is grounded; one end of the second capacitive load is connected with the direct-connection end of the orthocoupler and the other end is grounded. The ultra wide band fixed phase shifter based on a capacitive load has compact structure, small area occupation and small insertion loss, does not need extra power supply and logical control, and can be widely applied.
摘要:
A quadrature signal generator comprises a resistor-capacitor, RC, polyphase filter and an inductor compensation arrangement. The inductor compensation arrangement comprises a first inductor connected between the first and the third output terminals, and a second inductor connected between the second and fourth output terminals. The first and second inductors are arranged to compensate for a capacitive load on the output terminals when in use. A beamforming arrangement, a communication device and a base station are also disclosed.
摘要:
A two-stage, passive, RC polyphase filter for mm-wave quadrature LO generation is presented. The filter features an innovative, symmetrical layout structure, which is more robust to parasitics than the conventional layout. Layout parasitics which become important at mm-wave frequencies are identified and a compensated. Impedance variations and transfer functions are evaluated considering these dominant parasitics. More than 15 dB improvement in image rejection ratio is achieved in comparison with conventional layouts. Using the inventive techniques more than 35 dB of image rejection ratio over a bandwidth of 6 GHz is demonstrated in an outphasing transmitter at 60 GHz in 40 nm CMOS.