138 results about "RF modulator" patented technology

The present invention is directed to a non-intrusive data transmission network for use in a healthcare facility and method for implementing such network. Each individual patient's room is equipped with a set-top control device, a separate camera, microphone, control module camera control device. The SCD allows for a non-intrusive installation within a minimum amount of time. By utilizing the existing cable television infrastructure, the device creates a high-speed data network throughout the facility. The interface between the SCD and the CCD is accomplished through a standard interface for universally connecting auxiliary devices, such as USB, for enabling expandable, hot-pluggable Plug and Play serial device interfaces. These ports allow external devices such as the camera, microphone, infrared keyboard and privacy control unit to communicate with the SCD. Additional USB ports on the SCD allow for other devices to be connected to the network at a future time. Such devices include those for instrument monitoring, doctor information access or pharmaceutical prescription ordering. Visual information such as e-mail, web browsing, video and audio communications via web camera applications from family members, friends or other parties may be viewed by the patient from the in-room TV set by way of the internal RF modulator (and connecting to the Internet via the patient Internet server). The SCD switches from the standard cable TV channels to the SCD by way of an internal switch controlled by the patient from an infrared control. This control also enables or disables the camera to allow for privacy at times when such privacy is required from external Internet access. The system is configurable to offer this privacy to be layered from specific Internet or external users to the nurses, doctors or security department as the hospital desires.

A radio frequency (RF) transmitter uses two digital-to-RF conversion modules to convert digital baseband signals into RF signals. In cartesian mode, baseband signals are conveyed to the conversion modules for RF conversion. In polar mode, baseband signals are converted into amplitude and phase data parts. Phase data part is converted into I (inphase) and Q (quadrature) data parts to be converted into RF signals which are modulated in a power amplifier by amplitude data part through the power supply of the power amplifier. Each digital-to-RF module uses parallel unit cells to perform digital-to-analog (D / A) conversion and upconversion functions by an IF signal. Each unit cell, adapted to receive a control voltage indicative of a data signal value, is a mixer cell type converter having a differential data switch section connected in series to a differential LO (local oscillator)-switch pair. LO-switch is further connected in series to a current source.

A transmitter of a base station includes a data serial-to-parallel converter, M modulators, M beam formers, and transmission antennas. The data serial-to-parallel converter converts transmission data into M sequences. Each modulator modulates the transmission data. Each beam former weights the modulation signal to form directional beams. The transmission antennas narrow the beams and transmit the modulation signals in parallel (MIMO transmission). In a mobile station, a receiver has reception antennas for receiving data transmitted in parallel and an MIMO demodulator for demodulating the data.

A Wireless Neural Data Acquisition System for increased power efficiency, compact size, robust signaling and reliable transmission is shown and described. In one embodiment, the system includes a headstage, an RF receiver, an analog-to-digital converter, a digital signal processor, and a communication interface. The headstage includes at least one input pre-amplifier high-pass filter and amplifier, a multiplexer (MUX), an RF Modulator comprising a voltage control oscillator (VCO), a transmitting antenna, and a power supply. The RF receiver includes at least one receiving antenna, at least one bandpass filter, at least one amplifier, at least one attenuator, and an FM Demodulator.

A phase lock loop RF modulator system including a phase lock loop circuit having a phase detector circuit responsive to an input reference signal and a feedback signal, an oscillator circuit responsive to the phase detector circuit for providing an output signal, a forward path from the phase detector circuit to the oscillator circuit, and a feedback path from the oscillator circuit to the phase detector circuit. The system also includes a first modulation port coupled to the feedback path, a second modulation port coupled to the forward path, and a gain mismatch detection circuit responsive to modulation data and a phase error between the reference signal and the feedback signal for providing an indicator output signal that represents the gain mismatch between the first modulation port and the second modulation port.

A PM / FM modulator (100) includes an analog-to-digital converter (110) having an input terminal for receiving an analog input signal, and an output terminal, and a direct digital frequency synthesizer (120) having an input terminal coupled to the output terminal of the analog-to-digital converter, and an output terminal for providing a modulated output signal. In one form, an FM stereo modulator (200) includes a digital stereo modulator (210) and a direct digital frequency synthesizer (250). The digital stereo modulator (210) has a first input terminal for receiving a right analog input signal, a second input terminal for receiving a left analog input signal, and an output terminal for providing a digital signal having a stereo spectrum. The direct digital frequency synthesizer (250) has an input terminal coupled to the output terminal of the digital stereo modulator (210), and an output terminal for providing a modulated output signal.

Distributed and highly software reconfigurable CMTS (CMRTS) device, based on MAC and PHY units with FPGA and DSP components, for a HFC CATV network. The various CATV RF modulators, such as QAM modulators, may be divided between QAM modulators located at the cable plant, and remote QAM modulators ideally located at the fiber nodes. A basic set of CATV QAM data waveforms may optionally be transmitted to the nodes using a first fiber, and a second set of IP / on-demand data may be transmitted to the nodes using an alternate fiber or alternate fiber frequency, and optionally using other protocols such as Ethernet protocols. The nodes will extract the data specific to each neighborhood and inject this data into unused QAM channels, thus achieving improved data transmission rates through finer granularity. A computerized “virtual shelf” control system for managing and reconfiguring the FPGA and DSP based CMTRS units is also disclosed.

A radio frequency modulator based on direct frequency / phase modulation of output signal of a controllable oscillator (724) that is a part of a phase locked loop (PLL) provides a direct modulator that is able to operate over a wide frequency range with a flat frequency response. A modulation signal is digitally processed (721, 730) before injection to a high-pass path of a direct modulator. Applicability of digital signal processing is based on the fact that the modulation signal is a base band signal. Therefore, the modulation signal (702) occupies such a band in the frequency domain so that a sufficient ratio of a sampling rate to an upper edge frequency of the modulation signal can be achieved. Digital processing is used for compensating an effect of non-flat high-pass PLL transfer function and / or to perform pre-distortion of the input signal of a controlled oscillator to compensate an effect of non-linearity of a controlled oscillator.

A method and system for generating a frequency hopping electromagnetic signal based on a baseband data signal includes a frequency hopping pre-compensator. The frequency hopping pre-compensator determines a frequency hopping pre-compensation signal based on a desired frequency hopping sequence. The frequency hopping pre-compensation signal is combined with the baseband data signal to generate a pre-compensated baseband signal. An RF modulator modulates an RF carrier in accordance with the pre-compensated baseband signal to generate a modulated, frequency hopping RF carrier signal. An amplifier may then amplify the RF carrier signal as desired.

An electronic device includes a radio frequency (RF) modulator, a power amplifier, and a distortion correction circuit coupled between the RF modulator and the power amplifier. The distortion correction circuit includes a variable gain amplifier coupled between the RF modulator and the power amplifier, and an amplitude correction control loop. The amplitude correction control loop includes a first logarithmic converter having an input coupled to the RF modulator, a second logarithmic converter having an input coupled to an output of the power amplifier, and a difference circuit coupled to outputs of the first and second logarithmic converters for controlling the gain of the variable gain amplifier for correcting distortion in an output signal from the power amplifier.

The invention discloses a photonics broadband microwave IQ modulator and an operating method thereof. The method relates to the technical field of microwaves and the technical field of optical communication. The method is shown in an attached drawing, and comprises a laser diode (LD), a pulse duration modulation-dual parallel Mach-Zehnder modulator (PDM-DPMZM), an optical band pass filter (OBPF) and a photoelectric detector (PD). In the method, a pair of up-converters is constructed by the PDM-DPMZM and the OBPF, so that I-path and Q-path baseband waveforms can be directly modulated on a local oscillator (LO), and a broadband radiofrequency (RF) signal is obtained through the PD. The photonics broadband microwave IQ modulator has a simple structure; the bandwidth of an IQ baseband waveform is large; and the frequency of an LO signal can be tuned in a large range. A phase relationship between the two up-converters can be adjusted flexibly, so that the problem of IQ phase imbalance can be solved. Moreover, the RF signal generated by the IQ modulator has a large isolation degree on the LO, so that LO leakage can be restrained.

An identification card includes a fingerprint sensor, an antenna, a dual-mode radio frequency modulator connected to the antenna and digital circuitry having memory to store a digital word, the digital word including a representation of a fingerprint initially scanned by the fingerprint sensor to identify an individual associated with the identification card. The identification card further includes a control processor connected to the digital circuitry and the radio frequency modulator to communicate a signal to the antenna indicative of a successful match between the fingerprint initially scanned by the fingerprint sensor and newly scanned fingerprint. With such an arrangement, a technique is provided biometrically authenticating the identity of an individual passing through a checkpoint without requiring the individual to stop or exit a vehicle and eliminates the need for a central database of biometric data on individuals.

An RF modulator supporting wide-band signals includes IQ modulation by interleaving the in-phase and quadrature signals. The modulator can be implemented using an integrated circuit having a baseband in-phase stage that receives an in-phase analog input signal, a baseband quadrature stage that receives a quadrature analog input signal, and a switching mixer having a plurality of switches. The switching mixer receives in-phase and quadrature signals from the baseband in-phase stage and the baseband quadrature stage. The switching mixer produces a differential signal combining the in-phase and quadrature signals by interleaving the signals over a plurality of phases of a carrier period.

A phase lock loop RF modulator system including a phase lock loop circuit having a phase detector circuit responsive to an input reference signal and a feedback signal, an oscillator circuit responsive to the phase detector circuit for providing an output signal, a forward path from the phase detector circuit to the oscillator circuit, and a feedback path from the oscillator circuit to the phase detector circuit. The system also includes a first modulation port coupled to the feedback path, a second modulation port coupled to the forward path, and a gain mismatch detection circuit responsive to modulation data and a phase error between the reference signal and the feedback signal for providing an indicator output signal that represents the gain mismatch between the first modulation port and the second modulation port.