Abstract: A boost class-D amplifier includes a PWM modulator, a boost level controller coupled to the PWM modulator, a pre-driver coupled to the PWM modulator and the boost level controller, a system voltage source, an inductor coupled to the system voltage source, a first switch, a second switch, a third switch, a fourth switch, a first diode coupled between the third switch and a voltage ground, a second diode coupled between the fourth switch and the voltage ground, and a capacitor coupled between the first switch and the fourth switch. The PWM modulator is for receiving an input signal and generating a first modulated signal accordingly. The boost level controller is for receiving the first modulated signal and generating a second modulated signal accordingly. The pre-driver is for receiving the first modulated signal and the second modulated signal and generating control signals accordingly.

Abstract: A method for radio source scheduling implemented in a communication network, the method comprising steps of establishing a connection between a baseband unit (BBU) and at least one transceiving device; transmitting, by the BBU, a plurality of downlink packets according to a downlink scheduling of the BBU; arranging each of the downlink packets to a plurality of transceiving devices; receiving, by the transceiving devices, the downlink packets and transmitting, by the transceiving devices, a plurality of uplink packets; and receiving the uplink packets, by the BBU, according to the downlink scheduling of the BBU.

Abstract: A circuit board housing assembly includes a housing; a circuit board having an opening attached to the housing; and a board removal tool having a holding member, a rivet and a pin. The holding member has an aperture corresponding to the opening and the rivet is inserted in the opening and the aperture. The rivet has a head with a proximal end and a distal end and a central axis, the head has an internal passage extending parallel to the central axis from the proximal end to the distal end, and the distal end is mechanically connected to legs extending distally from the head and having an internal surface facing the central axis. When the pin is inserted into the internal passage along a direction from the proximal end towards the distal end, the pin applies force to the internal surface of the at least two legs in a direction perpendicular to the central axis.

Abstract: The present disclosure provides a satellite signal reception system comprising a low noise block down-converter for receiving satellite signals; a plurality of receivers configured to transmit the satellite signals from the low noise block down-converter to a display device; and a power splitter. The power splitter includes a first port electrically connected to the low noise block down-converter via a single cable; a plurality of second ports electrically connected to the plurality of receivers; a signal-distributing circuit electrically connecting the first port to the plurality of second ports; a plurality of power-supplying circuits electrically connecting the plurality of second ports to the first port; and a command-transmitting circuit electrically connecting the plurality of second ports to the first port, wherein the command-transmitting circuit includes a controller unit programmed to forward DiSEqC commands from the plurality of second ports to the first port in a first-in-first-out manner.

Abstract: A switchable radiator includes a dielectric substrate, a first conductive layer having a slot disposed over an upper surface of the dielectric substrate, a tunable dielectric layer disposed over the first conductive layer, and a second conductive layer disposed over the tunable dielectric layer. The tunable dielectric layer has a first dielectric constant at a first DC voltage and a second dielectric constant at a second DC voltage. The second conductive layer includes a first signal section, a second signal section, and an impedance-matching section connecting the first signal section and the second signal section. The operation method of the switchable radiator includes applying a first DC voltage to the tunable dielectric layer to enable the switchable radiator to radiate energy through the slot and applying a second DC voltage to the tunable dielectric layer to disable the switchable radiator from radiating energy through the slot.

Abstract: A tunable filter element comprises a resonator unit that defines a longitudinal axis, the resonator unit includes an inner conducting portion defining an inner shorting end along the longitudinal axis and an inner capacitive end opposing the inner shorting end, an outer conducting portion arranged around the inner conductor defining an outer shorting end along the longitudinal axis and an outer capacitive end opposite to the outer shorting end. The inner and the outer conductors maintain an annular gap there-between, and are coupled to form a shorting end at one end and a capacitive end at the other. The filter element further comprises a ferrite insert disposed between the inner and the outer conducting portions and substantially filling the annular gap, the ferrite insert being configured to receive a bias magnetic field in a direction substantially parallel to the longitudinal axis.

Abstract: A microwave resonant cavity includes a conductive shell with a screw hole having first threads and a screw having second threads configured to engage with the screw hole. The conductive shell defines a volume, the screw extends into the volume, the microwave resonant cavity has a resonant frequency, and the movement of the screw changes the resonant frequency. The first threads have a first pitch, and at least a portion of the second threads has a second pitch different from the first pitch.

Abstract: A laminated waveguide diplexer includes an upper conductive layer having a first slot and a second slot; a first line crossing over the first slot; a first shielding conductor disposed over the first line; a plurality of first conductive pillars connecting the upper conductive layer and the first shielding conductor; a second line crossing over the second slot; a second shielding conductor disposed over the second line; and a plurality of second conductive pillars connecting the upper conductive layer and the second shielding conductor.

Abstract: A laminated waveguide diplexer includes a first laminated waveguide, a second laminated waveguide, and a coupling metal connecting the first and second laminated waveguides. The first laminated waveguide has a first upper conductor with a first slot, and the second laminated waveguide has a second upper conductor with a second slot. The coupling metal includes a first line crossing over the first slot and a second line crossing over the second slot. In addition, the laminated waveguide diplexer further includes a first via connecting the first upper conductor and the first line, and a second via connecting the second upper conductor and the second line. The first and second vias are adjacent to the first and second slots, respectively, such that the first and second lines are short stubs for respective radio frequency signals propagating thereon.

Abstract: A multi-layer circuit board with a waveguide to microstrip transition structure includes a laminated structure having a plurality of dielectric layers, a top metal frame disposed over the laminated structure, a microstrip line disposed over the laminated structure, a bottom metal frame underlying the laminated structure, and a plurality of conductors electrically connecting the top metal frame and the bottom metal frame. The top metal frame defines a top cavity, the bottom metal frame defines a bottom cavity corresponding to the top cavity, and the microstrip line extends into the top cavity. The laminated structure includes an upper dielectric layer and at least one lower dielectric layer, wherein top cavity exposes a top surface of the upper dielectric layer, and the bottom cavity exposes a bottom surface of the at least one lower dielectric layer.

Abstract: An integral high frequency communication apparatus comprises a case, a waveguide apparatus having an extension portion, and a circuit board having a signal transmitting unit and a signal receiving unit. The transceiver module having two waveguide openings is retained in the case. The case has an opening through which the extension portion extends outside of the case. The integral high frequency communication apparatus can receive and transmit high frequency signals by the extension portion.

Abstract: A method of multipath compensation for digital pre-distortion (DPD) linearization suppresses linear distortion caused by reflected signals and distortion in transmitting and receiving paths. Reflection suppression suppresses effects of the linear distortion on the transmitting and receiving paths.

Abstract: A method of crest factor reduction using amplitude compression for multi carrier signals. Major elements of the inter-modulation distortion caused by amplitude suppression are removed to be outside of the desired signal band, and the peak amplitude is compressed, thus producing a signal with lower peak to average ratio for a required maximum error vector magnitude.

Abstract: A current source circuit includes a first transistor Q1, a second transistor Q2, a first resistor R1, and a second resistor R2. The first transistor Q1 has a first terminal (collector) coupled with the supply voltage (VCC), a second terminal (base) coupled with the first resistor R1, and a third terminal (emitter) coupled with the second resistor R2. The second transistor Q2 has a first terminal coupled with the second terminal of the first transistor Q1, a second terminal coupled with the third terminal of the first transistor Q1, and a third terminal coupled with the filtering circuit 39. The first resistor R1 is coupled between the supply voltage and a second terminal of the first transistor Q1. The second resistor R2 is coupled between a third terminal of the first transistor Q1 and the filtering circuit 39.

Abstract: A release device for detaching a male plug of a cable line from a female receptacle includes a holding portion, an accommodating portion, a connecting portion and an engaging portion. The accommodating portion includes a first guiding part that is configured for alignment between the accommodating portion and the male plug. The holding portion connects to the connecting portion that connects to the accommodating portion. The accommodating portion connects to the engaging portion, which includes a concave area that is configured for engaging the male plug.

Abstract: A Radio Frequency Identification (RFID) assembly includes an RFID reader/writer having a first micro-USB (Universal-Serial-Bus) connector and a mobile phone having a second micro-USB connector configured to electrically connect to the first micro-USB connector. In one embodiment of the present disclosure, the RFID reader/writer includes a circuit board having a first processor and a first USB controller, and an antenna board stacked on the circuit board, wherein the first USB controller electrically connects the first processor and the first micro-USB connector, and the antenna board includes a reverse F-shaped antenna. In one embodiment of the present disclosure, the mobile phone includes a second processor, and a second USB controller electrically connecting the second processor and the second micro-USB connector.

Abstract: A Dynamic Digital Pre-Distortion (DDPD) system is disclosed to rapidly correct power amplifier (PA) non-linearity and memory effects. To perform pre-distortion, a DDPD engine predistorts an input signal in order to cancel PA nonlinearities as the signal is amplified by the PA. The DDPD engine is implemented as a composite of one linear filter and N?1 high order term linear filters. The bank of linear filters have programmable complex coefficients. To compute the coefficients, samples from the transmit path and a feedback path are captured, and covariance matrices A and B are computed using optimized hardware. After the covariance matrices are computed, Gaussian elimination processing may be employed to compute the coefficients. Mathematical and hardware optimizations may be employed to simplify and reduce the number of multiplication operands and other operations, which can enable the DDPD system to fit within a single chip.

Abstract: A radio frequency front end circuit module for a receiver used in a digital television is disclosed. The radio frequency front end circuit module includes a switch set, a differential low noise amplifier, a filter, and a tuner. The switch set receives two differential signals. The differential low noise amplifier is electrically coupled to the switch set for amplifying the two differential signals. The filter is electrically coupled to the differential low noise amplifier for filtering out portions which are excluded in a predetermined bandwidth of the two amplified differential signals. The tuner determines how to control the switch set to select the two differential signals in the predetermined bandwidth according to the filtered differential signals. The present invention is capable of amplifying the received differential signals and rejecting noise which has the same phase as that of the received differential signals.

Abstract: A radio frequency transceiver includes a mixer circuit configured to convert an intermediate frequency signal into a radio frequency signal, a driver amplifier circuit configured to amplify the radio frequency signal from the mixer circuit, a temperature sensing circuit configured for sensing ambient temperature, and an attenuation circuit connected with the temperature sensing circuit, configured to decreasingly attenuate the radio frequency signal from the driver amplifier circuit as the ambient temperature increases.

Abstract: An angle adjustment apparatus for a dish antenna comprises a base, a first rotating frame, a second rotating frame, and a second rotation angle adjustment mechanism. The first rotating frame is fixed to the base, and can relatively rotate around the base with a first rotating angle. The second rotating frame is fixed to the first rotating frame, and can relatively rotate around the first rotating frame with a second rotating angle. The second rotation angle adjustment mechanism comprises a first screw rod, a screw nut post, and a second screw rod. One end of the first screw rod is fixed to the first rotating frame, and the other end is equipped with first threads and engaged with the screw nut post. One end of the second screw rod pivots on the second rotating frame, and the other end is equipped with second threads and engaged with the screw nut post. The first threads and second threads have different screw directions, or have the same screw direction but with different thread pitches.