985 results about "Power detector" patented technology

A wireless mobile terminal includes an antenna, a power amplifier coupled to the antenna, a power detector coupled to an output of the power amplifier, a phase shifter coupled between the output of the power amplifier and the antenna, and a controller coupled to the phase shifter. The power detector is configured to detect a power of a signal provided by the power amplifier. The controller is configured to adjust the phase shifter responsive to the detected signal power. More particularly, the controller may be configured to adjust the phase shifter to modify a phase component of a reflection coefficient of a load impedance at the power amplifier output without substantially altering a magnitude of the reflection coefficient. Related methods and computer program products are also discussed.

An RF device including a control loop for maximizing output power for each of several data rates or constellation types. The RF device includes a power detector, a power amplifier and a MAC that includes input and output adjust circuits. A power level value is generated from measured output power. The MAC compares an adjusted power level value with a set point value and generates an error value. The MAC adjusts a power control value based on the error value for controlling the gain of the power amplifier. The MAC uses a data rate signal indicative of a selected constellation type or data rate. The input adjust circuit stores one or more input adjustment values selected by the data select signal for adjusting the power level value. The output adjust circuit stores one or more output adjustment values selected by the data select signal for adjusting the power control value.

An apparatus (10) for supplying regulated voltage d.c. electrical power to an LED array (12) includes a rectifier (32) responsive to a.c. power for generating rectified d.c. power and a power factor correcting and voltage regulating buck/boost switchmode converter (38) responsive to the rectified d.c. power for generating regulated voltage d.c. power to illuminate the LED array (12). A battery backup system (62) receives the a.c. power applied to the rectifier (32) for charging a rechargeable battery (66) and sensing an a.c. power failure. A switch-over relay (82) is connected between the battery backup system (62) and the rectifier. Upon sensing a failure of the a.c. power, the battery backup system (62) controls the switch-over relay (82) to connect the battery backup system (62) to the rectifier (32) to provide d.c. power to the switchmode converter (38) to illuminate the LED array (12). A half wave power detector (88) causes the apparatus (10) to reduce regulated d.c. power to dim the LED array (12).

A two- (or multi) stage power amplifier receives a variable RF input signal, and outputs an optimized. RF output signal from, for example, a mobile handset. The output power level from the handset is predetermined, as known in the art, by the received control signal from a base station. The first power amplifier stage amplifies the variable RF input signal and outputs an RF signal, Vin, to a power detector circuit and an RF signal to the second or next amplifier stage. The power detect circuit amplifies the Vin signal and rectifies that signal with a linearly biased diode and provides a detect signal to a DC to DC converter. The converter responds by providing an optimum voltage bias, which is linearly related to the DC voltage detect signal from the power detector, to the output stage, and, if desired, to the first and/or other stages of the power amplifier that optimizes the output power level while meeting the required linearity specification. The battery current consumption is optimized through this automatic, dynamically control of the supply voltage for the power amplifier at each output power level through the DC to DC converter.

The present invention relates to a device and a method in a transmitter stage in a radio transmitter for modulating and amplifying an information signal for further transmission through a radio channel. The transmitter stage in the radio transmitter comprises a converting device (5) PCH, an amplifier control device (8) PAC, a power detector (13) and a power amplifier (2). Examples of the problems solved by the present invention are difficulties in reducing the power consumption, non-linearities in the output signal when using non-linear amplifiers in radio transmitters, and achieving a high signal-to-noise ratio in the output signal without connecting filter arrangements after such an amplifier. The solution according to the inventive method and device utilizes an information signal which has in earlier steps been divided in its polar components: a phase reference component signal (Ephr) and an amplitude component signal (Aamp). The phase reference component phase modulates a low noise high power signal source which has a constant amplitude. The amplitude of the obtained signal is then formed in an amplifier, which is controllable with the amplitude component signal (Aamp). Its current consumption is registered and compared to a control value for the current. The amplifier is controlled towards this control value.

An approach is provided for adaptive supply voltage control of a power amplifier. A voltage detector detects a voltage swing, and a power detector detects power. A controller is coupled to the voltage detector and the power detector. The controller receives a signal specifying a required output power and determines, using the detected voltage swing and the detected power, a supply rail voltage corresponding to the required output power at a particular loading condition. A converter applies the determined supply rail voltage for generating the required output power.

Current network switching architectures require communication with a higher level network control plane, which can be slow to reroute communications, resulting in unacceptable losses of communications for customers. Examples embodiments of the present invention reroute communications faster detecting optical power of an optical signal at optical switches coupled via optical communication paths, and causing at least one optical communication path between a first optical switch and second optical switch to switch to an alternative optical communication path, in part, through physical layer triggering in an event optical power at at least one of the first or second optical switches falls below a threshold level. Switching in response to physical layer triggering may result in reduced switching times and, consequently, faster restoration of communications to customers after a network fault interruption.

A wavemeter for determining a wavelength of an incident optical beam comprises four optical components, each being arranged in the incident optical beam or in a part of it, providing a path with a respective effective optical length, and generating a respective optical beam with a respective optical power depending on the wavelength of the incident optical beam. The optical powers oscillate periodically with increasing wavelength, and a phase shift of approximately pi/2 is provided between two respective pairs of the four optical components. Respective power detectors are provided, each detecting a respective one of the optical powers. A wavelength allocator is provided for allocating a wavelength to the incident optical beam based on the wavelength dependencies of the detected first, second, third, and fourth optical powers.

A fixing member, a power detector, and a controller are included. The fixing member is heated by a heating unit that generates heat when power is supplied by a commercial power and a capacitor. The power detector detects energy of power stored in the capacitor. The controller performs an identical control to reduce number of copies of an image formed (fixed) per minute (CPM) to a predetermined number (40 CPM) in any of three cases in which the energy is less than a threshold for starting electric discharge when a plurality of recording mediums is continuously passed through the fixing member, in which a cardboard paper is continuously passed, and in which an amount of data of an image to be transferred on the recording medium is large.

A wireless communication module for engaging in communications with a base station, the wireless communication module being incorporated into an information device having an antenna, includes a transmitter, a transmission power being controlled by the base station; variable impedance matching section arranged between an antenna connector connected to the antenna and the transmitter, which adjusts an impedance by changing a matching parameter for the variable impedance matching section; transmission power detector for detecting the transmission power; and a controller for adjusting the matching parameter based on the detected transmission power of the transmitter detected by the transmission power detector.

A multiband phone capable of transmitting a signal within a plurality of distinct frequency bands having a single wide frequency range power detecting device capable of measuring the power of the transmitted signal over all of the plurality of frequency bands. The multiband phone includes multiple power amplifiers, where each power amplifier amplifies the power of a signal transmitted within a different frequency band. A power amplifier controller is provided for controlling the amount of amplification performed by the power amplifiers, where a switching device switches the connection of the power amplifier controller to a selected power amplifier. The single wide frequency range power detecting device is connected to the output of the all of the power amplifiers through a switching device, where the switching device connects the power detecting device to the particular power amplifier selected for transmission. The power detector then measures the power of the signal transmitted and feeds the measured power back to the power amplifier controller. The power amplifier controller may then adjust the voltage driving the power amplifier connected thereto based upon any difference detected between the desired output power and the measured output power. The performance of the wide frequency range power detecting device is adjusted for the specific transmission frequencies utilized by the multiband phone in order to achieve optimal power detection sensitivity over all of the multiple frequencies.

The invention discloses a battery power saving method for a portable electronic product. The method comprises the following steps: detecting current battery power of a system; sending a low power prompt signal when the current battery power of the system is lower than a low power triggering threshold; and setting a power saving mode expected by a user according to the low power triggering threshold, wherein the power saving mode is associated with a plurality of sets of operation parameters and/or on-off states related to power consumption of the system. The invention further discloses a battery power saving apparatus for the portable electronic product. The battery power saving apparatus comprises a battery power detector, a low power prompting device and a power saving mode setting device. When it is detected that current battery power of the system is lower than the low power triggering threshold, the low power prompt signal is sent, and the power saving mode expected by the user is set according to the low power triggering threshold. On the basis of the apparatus, the invention also discloses a mobile terminal of the portable electronic product using the battery power saving apparatus. The mobile terminal guarantees that the user sets a correct power saving mode at the right time, so the purpose of battery power saving is realized in reality.

A discrete low-noise amplifier designed to operate in a mobile wireless environment uses two cascaded GaAs FETs to achieve 25 dB gain and 0.9 dB noise figure at 2.5 GHz. Active bias control circuitry responsive to monitored amplifier output power automatically and continuously adjusts the drain-source currents, and the load lines, of the cascaded FETs to (i) maintain power consumption at 33 milliwatts in nominal small-signal conditions, and to (ii) provide an elevated input third-order intermodulation intercept point (IP3) and a reduced noise figure during the presence of jamming. A 15 dB improvement in the input IP3 is achieved in large-signal operation. Amplifier operation is supported by an a.c. power detector of enhanced sensitivity and responsiveness because of un-grounded operation.

A two stage power amplifier circuit that employs both a DC to DC converter and sliding bias controller to improve power amplifier efficiency. The control signal that is generated by the power detector circuit to control the input voltage to the DC to DC converter is also used to provide the reference voltage that controls the sliding bias controller. The sliding bias controller reduces the quiescent current of the power amplifiers by reducing the bias currents, and thus the DC voltage at lower power output levels driving the power amplifiers. This causes the power amplifiers to operate at or near higher efficiency Class B operation at lower power output levels. As the power level increases, the sliding bias controller reduces its control on the bias currents so that the power amplifier can be driven at necessary higher power output levels.

We describe a variable bandwidth tunable optical spectral filtering device and associated method for selectively directing a portion of a wavelength multiplexed input signal, entering through one or more optical fibers, into one or more output signals provided to one or more optical fibers and/or electronic outputs. The optical filtering is accomplished using free-space diffractive wavelength de-multiplexing optics combined with a fixed (permanent) patterned structure located in the spectrally dispersed image plane. The structure can direct a selected spectral portion of the optical signal to one or more separate outputs, such as an optical fiber or power detector. A single active element in the optical path is used to spatially shift, or steer, the entire input spectrum at the dispersed spectral image plane, to control the portion of the input spectrum illuminating specific features on the permanent patterned structure. In one preferred embodiment, a device with a fixed selective area triangular shaped tilted reflective facet on a flat reflective surface is constructed such that the light reflected off the flat reflective surface and off the triangular reflective facet are selectively multiplexed back and directed to different output fiber ports. Inputs at different angles of incidence on the reflective structures may be deflected by the same structures to different output port fiber ports. A reconfigurable variable-bandwidth tunable optical add/drop multiplexing device is constructed using such a filtering device and an application of such an add/drop multiplexing in a optical transport network is demonstrated.

According to an example embodiment, an amplitude feedback loop may include an RF amplifier, a detector, a comparator, and a Q-enhancement cell. In an example embodiment, the RF amplifier has an output signal, and the detector has an input coupled to the output signal of the RF amplifier and is configured to detect a level of the output signal of the RF amplifier. The comparator circuit may receive as inputs a reference voltage and the output of the detector. Also, the comparator circuit is configured to output a control signal based on a difference between the reference voltage and the output signal of the power detector. The Q-enhancement cell may be coupled to the RF amplifier and have an input coupled to an output of the comparator circuit. A bias current of the Q-enhancement cell may be adjusted based on the control signal output by the comparator circuit.

A method and apparatus is provided for detecting the output power of a power amplifier. The output power is detected by detecting the absolute values of the voltage and current at the output of the amplifier and mixing the detected voltage and current to generate a signal related to the output power.