Class / Patent application number | Description | Number of patent applications / Date published |
455192100 | With frequency control | 23 |
20090221249 | METHOD AND ARRANGEMENT FOR SIGNAL PROCESSING IN A RECEIVER THAT CAN BE TUNED TO DIFFERENT CARRIERS - A method and circuit for signal processing in a receiver that can be tuned to different carriers, the method determining the energy of the adjacent carriers N+1 and N−1, wherein a carrier N contains a signal of interest and the receiver is tuned to it, from the digital signal, in that the energy value of the carriers N+1 and N−1 determined are compared with a threshold value, and in the case where the threshold value is exceeded, a frequency shift of the signal by +Δf or −Δf is effected in the second method step prior to the filtering, and the frequency shift thus produced is reversed by a frequency shift by −Δf or +Δf prior to the filtering, and the signal is decoded. | 09-03-2009 |
20090275300 | Receiver and receiving method of FM signal - A receiver of a frequency modulation (FM) signal includes an antenna, a tuner, an analog-to-digital converter (ADC), a demodulation module and a frequency offset estimation module. The antenna receives a FM signal. The tuner coupled to the antenna is for converting the FM signal into an intermediate frequency signal. The ADC coupled to the tuner is for converting the intermediate frequency signal into a digital intermediate frequency signal. The demodulation module coupled to the ADC is for demodulating the digital intermediate frequency signal into an audio signal based on a frequency offset compensation signal. The frequency offset estimation module coupled to the demodulation module is for generating the frequency offset compensation signal according to the audio signal. | 11-05-2009 |
20100035568 | ROBUST SENSING FOR DETECTING SIGNALS USING CORRELATION - To quickly and robustly detect the presence of an incumbent user and rapidly relinquish the spectrum to the incumbent user when necessary, carrier recovery is performed in a receiver of the secondary user's cognitive or software radio prior to performing correlation detection with an upsampled reference signal to correct for large frequency offsets and improve the performance of the correlation detector. To detect a received signal, a pilot value is added to a reference signal. The reference signal is upsampled to a sampling frequency of the received signal. The upsampled reference signal is correlated with a demodulated baseband signal to produce a correlation value. It is then determined whether the received signal is present if the correlation value is greater than a predetermined detection threshold value. | 02-11-2010 |
20100081405 | Frequency generation techniques - Techniques involving the generation of signals at particular frequencies are disclosed. For instance, an apparatus may include an oscillator module, a synthesizer module, and a control module. The oscillator module produces an oscillator signal having a first frequency. From the oscillator signal, the synthesizer module produces an output signal having a second frequency. A frequency multiplier corresponds to the first and second frequencies. The control module selects the first frequency and the frequency multiplier such that a difference between the second frequency and a nearest integer multiple of the first frequency is greater than a predetermined threshold. As a result, reductions in spurious outputs may be achieved. | 04-01-2010 |
20100178888 | RADIO WAVE RECEIVING APPARATUS - A radio wave receiving apparatus is provided with a tuning circuit for bringing a receiving frequency of an antenna tuned in to a frequency of a desired wave, a frequency converting circuit for mixing a local oscillation signal with the signal received through the antenna, thereby converting the received signal into an intermediate frequency signal, a feed back loop including at least a portion of the tuning circuit for feeding back the received signal, a controller for detecting a level of the intermediate frequency signal to change a frequency characteristic of the tuning circuit, thereby obtaining a tuning point corresponding to the desired wave, wherein, the controller brings the feed back loop in operation, thereby changing the frequency characteristic of the tuning circuit, and when two peaks of a level of the received signal are detected while the frequency characteristic of the tuning circuit is changed, the controller selects as a tuning point corresponding to the desired wave a tuning point at which one of the two peaks of the level of the received signal corresponding to a high-low relationship between the predetermined frequency of the local oscillation signal and the frequency of the desired wave is detected. | 07-15-2010 |
20100311372 | CORRELATION-DRIVEN ADAPTATION OF FREQUENCY CONTROL FOR A RF RECEIVER DEVICE - A frequency-control unit is used for controlling an external controllable reference-frequency source. The frequency-control unit includes a filter unit with a controllable filter parameter, which is configured to derive, using the filter parameter, from a frequency-error signal a frequency-control signal for minimizing the frequency error of the reference frequency; and a correlation unit, which is configured to determine from frequency errors of the reference frequency at different points in time a correlation measure indicative of a correlation between the frequency errors at the different points in time. The frequency-control unit is configured to adapt the controllable filter parameter of the filter unit in dependence on the determined correlation measure. The value of the filter parameter can depend also on a receiver path strength, such as an RSCP value. | 12-09-2010 |
20110028111 | METHOD AND SYSTEM FOR FREQUENCY TUNING BASED ON CHARACTERIZATION OF AN OSCILLATOR - Aspects of a method and system for frequency tuning based on characterization of an oscillator are provided. In this regard, a frequency of an oscillator in an integrated circuit may be controlled based on a first digital control word, a frequency of a tuned circuit may be controlled based on a second digital control word, and the second control word may be determined utilizing a mapping between the first control word and the second control word. The frequency of the oscillator and the tuned circuit may be controlled by adjusting a capacitance of the oscillator and tuned circuit, respectively. The mapping may be based on a relationship between the oscillator and the tuned circuit, such as logical and/or mathematical relationship between the capacitance of the oscillator and the capacitance of the tuned circuit and/or the relationship between the frequency of the oscillator and the frequency of the tuned circuit. | 02-03-2011 |
20110086603 | Radio Frequency Tuner - A RF tuner is described for handling RF signals in a broad frequency range and a broad power range while maintaining high linearity and tolerating high power blockers. A continuous feedback loop comprising a substantially linear LNA and a radio frequency RSSI can adjust the power of the RF signal on the RF side. On the IF side, a continuous feedback loop comprising a substantially linear, variable gain transconductor and a RSSI can adjust the power of the IF signal. | 04-14-2011 |
20110300820 | HIGH-FREQUENCY MODULE - A high-frequency module includes a switch IC. An antenna filter is connected to a common terminal of the switch IC and arranged adjacent to an antenna. The antenna filter is a low-pass filter whose attenuation band includes higher harmonic frequency bands of GSM1800/GSM1900 transmission signals and TDS-CDMA transmission signals. An individual-terminal filter is connected to one individual terminal of the switch IC. The individual-terminal filter is a low-pass filter whose attenuation band includes higher harmonic frequency bands of GSM850/GSM900 transmission signals. | 12-08-2011 |
20120220249 | Dynamic AC-Coupled DC Offset Correction - Systems are disclosed that utilize AC-coupled filtering to reduce DC offset, with aspects dynamically correcting instantaneous DC offset generated from the AC-coupled filtering. A DC offset correction circuit for an radio frequency (rf) receiver, comprising a switchable high pass filter configured to receive a signal, the switchable high pass filter including a plurality of high pass filters connected in parallel, wherein at least one of the plurality of high pass filters has a tunable corner frequency. | 08-30-2012 |
20130115902 | METHOD FOR TUNING AN OSCILLATOR FREQUENCY AND DEVICE IMPLEMENTING THE METHOD - A method for tuning an oscillator frequency produced in a radio-receiver chain is based on a slope analysis of a residual difference between the oscillator frequency and a carrier frequency of a radio-received signal. Depending on the slope value calculated, a bandwidth of a low-pass time-filtering that is effective for the frequency difference is increased or set back to a default value. The method provides an improved trade-off between tuning precision and dynamic behavior when the frequency difference drifts rapidly. | 05-09-2013 |
20150065074 | Simplified High Frequency Tuner and Tuning Method - A disclosed method tunes a signal from a channelized spectrum having a predetermined channel spacing. A signal of interest having a predetermined maximum bandwidth is mixed with a local oscillator signal, which has a frequency that is an integer multiple of the channel spacing or one-half of a channel spacing displaced from an integer multiple of the channel spacing. The local oscillator signal is selected to frequency translate the signal of interest to within a near-baseband passband whose lower edge is spaced from DC by at least about the maximum bandwidth of the signal of interest. Problems associated with 1/f noise, DC offsets, and self-mixing products are avoided or substantially diminished. Other methods and systems are also disclosed. | 03-05-2015 |
20150295603 | RECEIVER APPARATUS WITH BLOCKER DETECTION PATH PARALLEL WITH RECEIVER PATH AND ASSOCIATED BLOCKER DETECTION METHOD - A receiver apparatus includes a receiver path and a blocker detection path. The receiver path includes a down-converting stage. The blocker detection path includes a sensing circuit and a blocker detection circuit. The sensing circuit is arranged to sense a received radio frequency signal which has not yet been processed by the down-converting stage and generate a sensed signal accordingly. The blocker detection circuit is arranged to detect existence of a blocker signal according to the sensed signal and generate a blocker detection result indicative of the existence of the blocker signal when receiving the sensed signal. | 10-15-2015 |
20160164558 | PHASE-LOCKED LOOP WITH AN ADJUSTABLE OUTPUT DIVIDER - An apparatus relates generally to providing a divided signal output. In such an apparatus, a controller is coupled to receive a reference frequency count and a feedback frequency count to determine a difference therebetween to provide a control setting. A divider is coupled to receive the control setting to provide the divided signal output. The divider includes an adjustable load impedance. The control setting is coupled to adjust the load impedance of the divider to adjust a self-resonance frequency of the divider. | 06-09-2016 |
455192200 | Automatic (AFC) | 8 |
20100151806 | RF Filter with Low-IF Mixing, Tuning and Calibration - Radio-frequency (RF) circuits, methods and systems are implemented according to a variety of embodiments. According to one such embodiment, a radio-frequency (RF) receiver circuit is implemented with an adjustable RF filter circuit in a receive path of the RF receiver circuit. A local oscillator (LO) generates a LO signal and an RX_LO signal from the LO signal. A mixing circuit mixes a signal received from the adjustable RF filter circuit and the RX_LO signal. An intermediate-frequency (IF) circuit generates an IF_cal signal at the receiver circuit. A calibration circuit implements both a calibration mode and a receive mode. In the calibration mode, a calibration signal is injected into the receive path. A setting of the adjustable RF filter circuit is determined. In the receive mode, the calibration circuit disables the injection of the calibration signal into the receive path of the RF receiver circuit. | 06-17-2010 |
20100273441 | SYSTEMS AND METHODS FOR TUNING AN ANTENNA FOR A FREQUENCY MODULATION TRANSCEIVER - Systems and methods for tuning an antenna for a frequency modulation (FM) transceiver are provided. A representative system includes: a network of electrical adjustable passive components that receives and sends radio frequency (RF) signals to a receiver circuitry via the network of electrical adjustable passive components. The receiver circuitry determines the received signal strength indication (RSSI) of the RF signal. The system further includes a transmitter circuitry that transmits RF signals via the network of electrical adjustable passive components, and a peak detector circuitry that receives and determines a voltage output of the RF signals from the variable capacitors. An auto-tune circuitry receives the RSSI and output value from the receiver circuitry and the peak detector circuitry, respectively. The auto-tune circuitry is configured to adjust capacitance values of at least one of the serial variable capacitor and the parallel variable capacitor based on the RSSI and the voltage output during the reception and transmission of the RF signals, respectively. | 10-28-2010 |
20110230153 | Providing Channel Filtering In An Automatic Frequency Control Path - In one embodiment, the present invention includes a method for filtering an incoming signal in a channel filter of an automatic frequency control (AFC) loop to obtain a filtered incoming signal, generating a frequency offset from the filtered incoming signal in the AFC loop, removing the frequency offset from the incoming signal to obtain an adjusted signal, and providing the adjusted signal to an input of the channel filter. | 09-22-2011 |
20120252388 | FREQUENCY SWITCHING METHOD AND APPARATUS FOR RADIO DATA SYSTEM - A method and an apparatus for switching from the main frequency to an Alternative Frequency (AF) providing the same station is provided. The method includes measuring a received signal strength of a main frequency, receiving at least one alternative frequency list, establishing an accumulated alternative frequency list including all previously received alternative frequency lists, comparing the received signal strength of the main frequency with a predefined reference received signal strength, and attempting, when the received signal strength of the main frequency is less than the reference received signal strength, switching to an alternative frequency in the accumulated alternative frequency list. | 10-04-2012 |
20120302189 | AUTOMATICALLY CONTROLLABLE, FREQUENCY TUNABLE FILTER - A frequency tunable filter is disclosed. The disclosed filter comprises a filter unit having a sliding member so as to be capable of tuning a frequency band of a frequency signal being filtered; a communication module configured to receive a control signal for controlling the tuning of the frequency band; and a control unit configured to control the tuning of the frequency band by moving the sliding member based on the control signal. With the disclosed filter, the tuning of the filter may be performed automatically by way of control signals transmitted from a remote location. | 11-29-2012 |
20140141738 | SELF-TUNING AMPLIFICATION DEVICE - Radio frequency (RF) self-tuning amplification devices and methods of amplification for an RF input signal are disclosed. In one embodiment, the RF self-tuning amplification device has a first RF amplifier, a reference RF amplifier, and a tuning circuit. The first RF amplifier includes a first RF amplification circuit to generate an amplified RF output signal from the RF input signal, and a tunable parallel resonator tunable so as to shift an RF output signal phase of the amplified RF output signal. The reference RF amplifier includes a second RF amplification circuit that generates a reference RF signal from the RF input signal, and a resistive load, so that the reference RF signal has a reference RF signal phase. The tuning circuit is configured to tune the tunable parallel resonator to reduce a phase difference between the RF output signal phase and the reference RF signal phase. | 05-22-2014 |
20140148111 | ELECTRONIC DEVICE AND METHOD FOR AVOIDING RF INTERFERENCE - An electronic device which is capable of adjusting the working frequencies of electronic components of a device so as to avoid interference with a received RF signal within a particular range. The electronic device includes a detecting signal and a processor. The detecting unit detects whether a working frequency of an electronic component of the electronic device falls within the predetermined frequency range of the received RF signal. The processor adjusts the working frequency of the electronic component to prevent the received RF signal from being interfered if the working frequency of the electronic component falls with the predetermined frequency range. A method for avoiding RF interference is also provided. | 05-29-2014 |
20140220919 | AUTOMATIC FREQUENCY CONTROL METHODS AND APPARATUS - Embodiments include Direct-Conversion Receiver (DCR) apparatus, and methods for performing automatic frequency control based on a received signal. An initial frequency offset value is selected from a lookup table and applied to the receiver's local oscillator. Digital samples are generated based on the received signal, and stored in a buffer in sequential order. A DC estimator performs multiple iterations of a DC component estimation process. The process includes iteratively applying an analysis window to more recently-stored, buffered samples, in order to identify a set of the buffered samples. Within the set of buffered samples, an intermediate value between the amplitudes of two samples is determined (e.g., samples having the largest and smallest amplitudes). Between at least some of the multiple iterations, the number of samples that defines the size of the analysis window is increased. | 08-07-2014 |
455192300 | Fine tuning | 1 |
20100056088 | Simplified High Frequency Tuner and Tuning Method - A disclosed method tunes a signal from a channelized spectrum having a predetermined channel spacing. A signal of interest having a predetermined maximum bandwidth is mixed with a local oscillator signal, which has a frequency that is an integer multiple of the channel spacing or one-half of a channel spacing displaced from an integer multiple of the channel spacing. The local oscillator signal is selected to frequency translate the signal of interest to within a near-baseband passband whose lower edge is spaced from DC by at least about the maximum bandwidth of the signal of interest. Problems associated with 1/f noise, DC offsets, and self-mixing products are avoided or substantially diminished. Other methods and systems are also disclosed. | 03-04-2010 |