Abstract: An interface circuit includes a first amplifier circuit comprising a first input terminal configured to receive a first input signal, a second input terminal configured to receive a second input signal, a first output node configured to output a first output signal, a second output node configured to output a second output signal, and a variable impedance circuit comprising a first impedance circuit connected to the first output node, and a second impedance circuit connected to the second output node. A code generator circuit is configured to generate a first control code and a second control code. The first impedance circuit is configured to adjust an impedance thereof based on the first control code, and the second impedance circuit is configured to adjust an impedance thereof based on the second control code.

Abstract: A user equipment (UE) receives, from a base station, a network power mode configuration and receive control signaling indicating for the UE to switch to the network power mode configuration. The UE communicates with the base station based on the network power mode configuration in response to the control signaling. A base station transmits, to a UE, a network power mode configuration, and transmits control signaling indicating for the UE to switch to the network power mode configuration. The base station communicates with the UE based on the network power mode configuration in response to the control signaling.

Abstract: The present disclosure provides a channel monitoring method and a channel monitoring apparatus. The method is applied to a base station and includes: configuring a first discontinuous reception (DRX) parameter for a terminal for channel monitoring; determining a first power saving signal for indicating the first DRX parameter; sending the first power saving signal to the terminal for the terminal to determine the corresponding first DRX parameter based on the first power saving signal and perform corresponding channel monitoring based on the first DRX parameter.

Abstract: A noise detecting circuit including an amplifier circuit, a filtering circuit and a comparing circuit. The amplifier circuit is arranged to amplify an input signal and output an amplified signal, wherein the input signal is received from a circuit to be detected and indicates a noise level of the circuit to be detected. The filtering circuit is coupled to the amplifier circuit and arranged to filter the amplified signal and output a filtered signal. The comparing circuit is coupled to the filtering circuit and arranged to compare the filtered signal to a reference voltage and output an output signal indicating the noise level of the circuit to be detected.

Abstract: A convenience controller activates a small zone high precision welcoming detecting function (with high current utilization) in response to a detected arrival of an authorized user into a larger zone low precision approach region around a vehicle (with low current utilization). A short range transmitter broadcasts a polling signal covering the region. The short range transmitter has an approach pending mode wherein the polling signal is broadcast according to a first repetition and a baseline mode wherein the polling signal is broadcast according to a lower repetition. The short range transmitter has a first power drain in the approach pending mode. A wireless communication system is configured to monitor for user activity outside the approach region corresponding to proximity to the approach region. If the short range transmitter is in the baseline mode when the activity is detected, then the short range transmitter switches to the approach pending mode.

Abstract: Examples described may relate to methods and systems for gesture based switch for machine control. Some machines may be operated by computing devices that include touchscreens, and a graphical user interface (GUI) is provided for enabling control of the machines. Within examples, a disconnect switch can be incorporated into the GUI. As one example, to initiate operation of a machine, such as a robotic device, a user may be required to contact the touchscreen at a location and then trace out a pattern. To enable continued operation of the machine, the GUI may require the user to maintain contact with the touchscreen at a “goal” position. If contact with the touchscreen is broken (e.g., for more than a threshold amount of time), the machine operation may be halted, and the process to initiate operation can be performed again on the touchscreen to cause the machine to resume operation.

Abstract: A convenience controller activates a small zone high location precision welcoming detecting function (with high current utilization) in response to a detected arrival of an authorized user into a larger zone low location precision welcoming detecting function (with low current utilization) approach region around a vehicle. A short range transmitter broadcasts a polling signal covering the region. The short range transmitter has an approach pending mode wherein the polling signal is broadcast according to a first predetermined repetition and a baseline mode wherein the polling signal is broadcast according to a lower repetition. The short range transmitter has a first power drain in the approach pending mode. A wireless communication system is configured to monitor for user activity outside the approach region corresponding to a potential user entry into the approach region, wherein monitoring by the wireless communication system has a lower power drain.

Abstract: A method includes encoding a session identifier into a uniform resource identifier (URI) associated with a TCAP Begin message request originating at an application server, where the session identifier identifies a communication session. The method also includes transmitting the TCAP Begin message request from the application server to a transaction capabilities application part (TCAP) interface and receiving a TCAP Continue message request from the TCAP interface with the TCAP Continue message request including the encoded URI. The method includes correlating the TCAP Continue message request to the communication session that originated the Begin request identified by the session identifier in the received URI and routing the TCAP Continue message request to the communication session.

Abstract: The illustrative embodiments described herein provide a method, apparatus, and computer program product for customizing settings in a communication device for a user. In one illustrative embodiment, the process identifies a user profile to which a user belongs. The process identifies a set of custom communication device settings associated with the user profile. The process also sets a current set of communication device settings for a set of functions in a communication device to the set of custom communication device settings. In one embodiment, identifying the user profile to which the user belongs includes identifying the user profile to which the user belongs based on one or more characteristics of the user.

Abstract: A first communication device receives a communication from a second communication device. The communication could be part of the signaling used to establish a call to the second communication device or an audio signal that the second communication device conveys after its user has answered the call and started speaking. Based on the communication from the second communication device, the first communication device provides a user-discernible indication regarding the environment in which the second communication device is being used, such as an indication that the second communication device is being used with a speakerphone. If the second communication device is being used in a vehicle, the first communication device may also provide a user-discernible indication regarding the operational status of the vehicle, such as whether the vehicle is in motion and/or the number of occupants in the vehicle.

Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.

Abstract: Methods, systems, apparatus and computer program products are provided to facilitate power control in wireless communication systems. A cell that is experiencing excessive interference conditions may generate an over-the-air overload indicator indicative of interference conditions at the cell. The over-the-air overload indicator is received by one or more user equipment in a neighboring cell. In response, the user equipment determines adjustments to its transmit power that reduce and/or eliminate the interference. This determination may be carried out by the user equipment, by the serving base station, or through cooperation between the user equipment and the serving base station. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the disclosed subject matter. Therefore, it is to be understood that it should not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A system and method are provided for transmitting a broadband interference signal and allowing communication through the transmitted interference signal. The system includes an interference transmitter for transmitting the interference signal, the interference transmitter having a transmitter feeder and a first antenna; a radio receiver for receiving a radio signal, the radio receiver having a radio feeder and a second antenna collocated with the first antenna of the interference transmitter; a steering signal generator for introducing at least one steering signal into the interference signal at the transmit feeder; a first directional coupler for sampling a portion of the interference signal that includes at least one of the steering signals; a negative feedback loop for adjusting the amplitude and phase of the sampled portion of the interference signal; and a second directional coupler for coupling the adjusted sampled portion of the interference signal into the radio feeder.

Abstract: The present invention relates to mobile communication technologies, and in particular, to a method, base station and system for sending information. The method includes: obtaining discontinuous reception (DRX) parameter of a terminal; determining discontinuous transmission (DTX) parameter of the base station according to the DRX parameter; and sending pilot and broadcast information periodically according to the DTX parameter. The technical solution under the present invention saves time-frequency resources, reduces interference on neighboring cells, and saves electric power.

Abstract: A channel scanning technique and apparatus provides audio hole suppression in two-way radio communications. Upon detecting the absence of a carrier signal on a priority channel during a priority scan mode of operation, a training waveform is constructed upon returning to the home-channel. The training waveform is applied to audio shaping filters within an audio lineup to suppress transients and minimize or eliminate the occurrence of audio pops at a speaker output thereby reducing the audio hole.

Abstract: A base transceiver station (200) that transmits same data through a common channel shared by a transmission path includes a cell total transmit power detector (41) that detects, with respect to each of a plurality of cells, a total amount of the transmit power for transmitting the data to mobile stations (300) located inside each of the cells, a relative value information receiver (42) that receives relative value information for relatively correcting the total transmit power, from the base transceiver station controller, and a weight adjustment and power determination unit (43) that corrects the total transmit power for transmitting the data with respect to each cell, based on the relative value information received by the relative value information receiver and the total transmit power detected by the cell total transmit power detector, and determines a modified total transmit power.

Abstract: A wireless communication device for use in a noisy or harsh environment in connection with a cellular telephone is disclosed. The wireless communication device provides enhanced audio broadcasting capabilities for an operator of the device by providing a larger, more powerful speaker than that typically found in a cellular telephone. The apparatus of the present invention improves cellular telephone usage in the typically noisy and harsh environment found while operating a boat. The present apparatus further provides a half-duplex mode of communication to further reduce ambient noise experienced while using a cellular telephone in a noisy environment In another embodiment, the apparatus is connectable to a variety of external devices and is capable of operating the external devices and providing internet access for a variety of external devices through a cellular telephone connection In at least one embodiment, the present invention is connectable to any transceiver.

Abstract: An output signal SHS is secondarily amplified by a high-frequency amplifier AMP3 and an output signal SHR is secondarily amplified by an AMP4 for which high-frequency side amplitude reducing means is taken. In this case, the AMP4 has small gain of a high-frequency region and its output SHR-2 is reduced in amplitude. However, a high-frequency noise has a frequency higher than that of a carrier wave SH and the amplitude of a noise NzB becomes smaller. The other output signal SHS is directly amplified by the wideband amplifier AMP3. The width of an SHS-2 and the width of the SHR-2 are adjusted by amplitude adjusting means throughout the whole region and then mutually added by both signals addition amplifying means again so that the amplitude of the output signal SHS is adjusted to the SHR-2, and a predetermined threshold value is set to extract the noises.

Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.

Abstract: Exemplary methods and systems are described that may be employed in a radio access network in order to aggregate the power-control messages from the sectors in a mobile station's active set, and provide an aggregate reverse-link power-control indication, in all active sectors. To do so, an exemplary base station may periodically determine an appropriate reverse-link power adjustment for a mobile station. However, rather than immediately send power-adjustment indications to the mobile station, each base station serving an active sector is preferably configured to send the power-adjustment indication to mobile switching center. The mobile switching center then determines an aggregate power-control indication for the mobile station. The aggregate power-control indication may then be transmitted to the mobile station in each of the mobile station's active sectors.

Abstract: A method and system for conserving battery power in a portable communication device. When a user puts the device into a media player mode such as by invoking a media player application on the device, the device will automatically reduce the extent to which it engages in background wireless transmissions, such as radio link control messaging, presence update messaging, and so forth, to help conserve battery power. In turn, when the device exits the media player mode, the device may then automatically revert to its normal extent of background wireless transmission.

Abstract: A system and method is provided for establishing a call to a wireless directory number which is either a non-geographic directory number or a non-dialable directory number. A call is initiated from a wireline telephone to a geographic-based local access directory number. A signaling node associated with the dialed local access DN sends a location request that includes the local access DN to an HLR. The HLR obtains the wireless DN from an internal database in which the wireless DN is associated with the local access DN. The HLR utilizes the wireless DN to receive a temporary local directory number (TLDN) from visitor location register, associates the TLDN with the local access DN and forwards the TLDN to the signaling node, which relays the TLDN to the originating switching node. The call connection is then established directly from the originating switching node to a visited cellular switch using the TLDN.

Abstract: Methods and systems are provided for dynamic adjustment of the pilot-channel, paging-channel, and sync-channel transmission-power levels based on forward-link and reverse-link RF conditions. In an exemplary embodiment, a base station provides service on a carrier in a wireless coverage area, and computes both an Ec/Ior value and a reverse noise rise (RNR) value for the carrier. Based at least in part on the Ec/Ior value and at least in part on the RNR value, the base station adjusts at least one of a pilot-channel power level, a paging-channel power level, and a sync-channel power level for the carrier. As an example, if (a) Ec/Ior is above a first threshold and (b) RNR is below a second threshold, the base station may increase all three of the power levels, so as to improve service quality and coverage, among other advantages.

Abstract: A method for controlling packet service setup includes the steps of: transmitting a packet service request message containing a requested QoS to a packet service node by a mobile communication terminal; transmitting to the mobile communication terminal a packet service request response message including an assigned QoS determined in consideration of the requested QoS and network resources contained in the message received by the packet service node; comparing one or more parameter values among parameters contained in the assigned QoS contained in the packet service request response message from a mobile communication network with corresponding one or more parameter values among parameters contained in the QoS requested by the mobile communication terminal; and transmitting a packet service cancel request message if a difference between the parameter values is greater than or equal to a preset value.

Abstract: In an adaptive array terminal, at least one of two antennas (ANT#1, ANT#2) is a movable antenna. A display unit (6) of the terminal displays reception levels of, or level difference between, the two antennas. Thus, it becomes possible for a user to adjust an angle of the antenna such that reception levels of the two antennas come closer to the same level. Alternatively, a control unit (8) of the terminal automatically adjusts the antenna angle so that reception level difference between the two antennas becomes not higher than a prescribed value.

Abstract: Disclosed are a method of controlling packet service setup and a mobile communication system. The method includes the steps of: transmitting a packet service request message containing a requested QoS to a packet service node by a mobile communication terminal; transmitting to the mobile communication terminal a packet service request response message including an assigned QoS determined in consideration of the requested QoS and network resources contained in the message received by the packet service node; comparing one or more parameter values among parameters contained in the assigned QoS contained in the packet service request response message from a mobile communication network with corresponding one or more parameter values among parameters contained in the QoS requested by the mobile communication terminal; and transmitting a packet service cancel request message if a difference between the parameter values is greater than or equal to a preset value.

Abstract: A radio terminal adjusts its data transmit power in response to received power control commands which specify a maximum transmit power level. The commands may be addressed to an individual radio terminal by means of a first address, or addressed to a group of radio terminals by means of a second address. In order that the data transmit power of an individual radio terminal is not disrupted by the commands addressed to a group, the radio terminal operates in two states. In the first state the radio terminal responds to commands comprising the first address and does not respond to commands comprising the second address. In the second state the radio terminal responds to commands comprising the second address. The radio terminal transfers from the first state to the second state in response to receiving a command comprising the first address and a predetermined value.

Abstract: A signal processing device includes: a speaker amplifier for amplifying a reception voice; a reception voice attenuator for attenuating the reception voice inputted to the speaker amplifier during a voice transmission mode; a reception voice detection circuit for detecting the reception voice outputted from the speaker amplifier; a microphone amplifier for amplifying a transmission voice inputted to a microphone; a transmission voice attenuator for attenuating the transmission voice outputted by the microphone amplifier during a voice reception mode; a transmission voice detection circuit for detecting the transmission voice outputted by the microphone amplifier; and a discriminator for discriminating the mode to be operated among the voice transmission mode and the voice reception mode on the basis of detection outputs from the reception voice detection circuit and the transmission voice detection circuit.

Abstract: A system and method is provided for establishing a call to a wireless directory number (982) which is either a non-geographic directory number or a non-dialable directory number. A call is initiated from a wireline telephone (155) to a geographic-based local access directory number (994, 996). An originating switching node (810) recognizes the local access directory number (994, 996) as an AIN trigger, and thereafter identifies a signaling node (820) that is associated with the dialed local access DN (994, 996). The signaling node (820) sends a location request that includes the local access DN (994, 996) to an HLR (130). The HLR (130) obtains the wireless DN (982) from an internal database (990) in which the wireless DN (982) is associated with the local access DN (994, 996). The HLR (130) utilizes the wireless DN (982) to receive a temporary local directory number (TLDN) from visitor location register (140).

Abstract: A squelch circuit for operating at high speed and at high frequencies includes a squelch input unit, a low swing pre-amplifier and a sampling and decision circuit. The squelch input unit pre-processes the positive and negative signals of an input signal to generate four pre-processed signals that are paired and sent to the low swing pre-amplifier. The outputs of the low-swing pre-amplifier are then over-sampled by the sampling and decision circuit. Multi-phase clocks are used to control the over-sampling in the sampling and decision circuit. A logic circuit then determines if the state of the input signal based on multiple samples.

Abstract: An electrical circuit detects a “squelch,” or “out-of-band,” state of a differential signal pair having a positive (“p”) signal line and a negative (“n”) signal line. In one embodiment of the invention, a first and a second comparator each have positive inputs driven by the positive and negative signal lines, respectively. The negative inputs of the comparators are driven by the outputs of separate digital-to-analog converters (DACs) which are set to a lower squelch threshold voltage. The outputs of the comparators then drive the inputs of a logical AND gate, the output of which indicates the current squelch state of the differential signal pair.

Abstract: A high sensitivity of a Super-Regenerative Radio Frequency Receiver and its method is provided in the embodiment of the present invention. By using a common-mode feedback circuit and by replacing the rectifier with a feedback integral-rectifier, the rectifier, the low-pass filter, and the slicer will not be saturated during operation so that the output of the slicer is correctly generated, and the sensitivity of the Super-Regenerative Radio Frequency Receiver is greatly improved as a result.

Abstract: A tuneable radio and method for automatically adjusting the seek sensitivity alignment for seek operations. The radio has a radio receiver for receiving broadcast radio wave signals, and a tuner adjustable for selecting from a plurality of radio wave signal channels. A detector detects signal strength of the received radio wave signals, and a seek input allows a user to initiate a seek operation to select a signal channel having a signal strength exceeding a seek sensitivity threshold. A controller calculates an average signal value and adjusts the seek sensitivity threshold based on the average value. The controller adjusts the seek sensitivity when it is determined that the radio has travelled beyond a minimum distance.

Abstract: A squelch circuit with an adjustable reference level, having an input level comparator with a first, a second, a third and a fourth current input terminal, a first and a second input terminal, and an output terminal. A first current source is coupled between the first current input terminal and an operation voltage. A second current source is coupled between the second current input terminal and the operation voltage. A third current source is coupled between the third current input terminal and a ground terminal. A fourth current source is coupled between the fourth current input terminal and the ground terminal. A bias generator is coupled to the first, second, third and fourth current sources to generate current control signals thereto according to a reference current and control bits, such that the first, second, third and fourth current sources generate the same current, which adjusts the reference level.

Abstract: A receiver for broadcast signals, e.g. DAB, FM, DVB, and digital or analog short-wave RF broadcast signals according to the present invention includes a polyfunctional circuit (5) that can be switched into three modes and performs the digital frequency demodulation which is needed for the reception of a frequency modulated signal in a first mode A, a digital frequency adjustment of the receiver in case of the reception of a digital or analog modulated broadcast signal like DAB, DVB, DRM or AM in a second mode B and the digital frequency adjustment and the digital gain control of the receiver which is needed in case of the reception of a digitally modulated broadcast signal like DAB, DVB, DRM in a third mode C. Depending on the needed functionality not all of these modes need to be realized. Nevertheless, the same hardware will be used for different purposes although the circuit is realized with an optimized amount of hardware to realize an efficient receiver.

Abstract: A squelch circuit with an adjustable reference level, having an input level comparator with a first, a second, a third and a fourth current input terminal, a first and a second input terminal, and an output terminal. A first current source is coupled between the first current input terminal and an operation voltage. A second current source is coupled between the second current input terminal and the operation voltage. A third current source is coupled between the third current input terminal and a ground terminal. A fourth current source is coupled between the fourth current input terminal and the ground terminal. A bias generator is coupled to the first, second, third and fourth current sources to generate current control signals thereto according to a reference current and control bits, such that the first, second, third and fourth current sources generate the same current, which adjusts the reference level.

Abstract: According to an embodiment of the invention a circuit that is to be coupled to a reference voltage line. The circuit includes a noise coupling circuit that is to couple noise from the circuit to a reference voltage line based upon whether a driver is driving a data line.

Abstract: A two-way radio (1) that has a radio frequency receiver (2) having a modulated radio frequency signal output and a variable bandwidth filter (3) with an input coupled to the modulated radio frequency signal output. The radio (1) also has demodulator circuitry (4), a speaker (6) and processing circuitry (5). In use when the radio (1) is operating in squelch mode, the processing circuitry (5) controls the variable bandwidth filter (3) to have a first bandwidth and when in unsquelch mode the processing circuitry (5) controls the variable bandwidth filter (3) to have a second bandwidth which has a smaller frequency range and the first bandwidth.

Abstract: An apparatus (30) and method minimize voice delay by combining comfort noise with subframe insertions to fill gaps in speech and maintain a minimum delay for packets arriving late. When a packet is late, short durations of sound are repetitively inserted until the late packet arrives. When the late packet finally arrives, the durations of future speech pauses are modified so there is no voice degradation.

Abstract: A radio receiver operable for communication in a radio system in which information is transmitted on respective channels in bursts. Each burst has a field for enabling the radio receiver to synchronise therewith. The radio receiver has an adjustable internal clock for timing receiving signals. Adjustment of the internal clock can be suspended if an error field in a received signal indicates that a signal received is not a valid burst.

Abstract: A method and apparatus for controlling transmission power levels in a mobile communication system. The method provides for a closed-loop power control method. A mobile station provides information on the quality of the signal received from the base station, and the base station responds by adjusting the power allocated to that user in a shared base station signal. The transmission power is adjusted initially by a large increment and then ramped down at an increasingly decreasing rate. The mobile station also provides information to the base station as to its relative velocity and the base station adjusts its transmission power in accordance with this velocity information.

Abstract: A receive squelch circuit detects a pulse width of an input data signal to prevent errors from occurring during detection of received data. The squelch circuit adds a function of detecting a pulse width to an input side to detect normal and abnormal pulse signals of received data and adjust the squelch circuit operations. The squelch circuit includes a plurality of current sources for each supplying a predetermined amount of current in accordance with a supplied power and a plurality of MOS transistors for detecting a pulse width of an input differential data signal. A plurality of voltage comparators compares the detected pulse width of the input differential data signal with a standard value and judges whether the detected pulse width is normal.

Abstract: In a portable telephone, a voice filter is connected to an antenna through a receiving circuit. A filter is connected to the voice filter through a switching circuit and filters the voice signal from the voice filter to produce a filtered voice signal. The filter has a first cut-off frequency when the filter is supplied with a first clock signal. The filter has a second cut-off frequency smaller than the first cut-off frequency when the filter is supplied with a second clock signal. A telephone receiver is connected to the filter through an amplifier. A clock generating circuit is connected to the filter and generates the first clock signal when is supplied with a first frequency control signal. The clock generating circuit generates the second clock signal when is supplied with a second frequency control signal.

Abstract: An adaptive digital squelch system, responsive to ambient RF background noise, that automatically adjusts the receiver squelch level during intervals when no valid signal is being received. A valid signal is considered to be a signal that is greater than the receiver squelch level and which contains an audio signal at a specific frequency; otherwise, the signal is considered noise. When the invention detects the absence of a valid signal, the squelch level is periodically calculated by averaging multiple noise signal levels at multiple frequencies.

Abstract: A receiver has a random counter, which outputs a timer signal to a control circuit. A zero-cross point detection circuit generates a detection signal which is input to the control circuit. When the random counter outputs a timer signal and the zero-cross detection circuit detects a zero-cross point, a muting function is activated. Simultaneously, different frequencies are scanned for broadcasts containing the same program and having higher field strengths. If on re-checking zero-cross point detection, a zero-cross point is found or a predetermined interval has expired, then the muting function is deactivated. The frequency with the greater field strength is selected.

Abstract: A wireless communications receiver having an adaptive squelch system and operable in multiple states including a receiver (11) that provides a received signal when operating in a clear (unscrambled) state and when operating in a secure (scrambled) state; a squelch function (13) that generates an unsquelch signal when the received signal satisfies a quality level; and a controller (15) that sets the quality level to a predetermined level that corresponds to the receiver operating state.

Abstract: A fast acting noise squelch control circuit for FM radio receivers samples the noise above the audio band to determine the presence of an RF carrier. The detected noise signal is integrated by a low-pass frequency gain integrating filter and compared, using a high gain differential amplifier, against a preset squelch threshold voltage to provide a signal indicative of the presence or absence of a received carrier. The output of the integrating filter is initialized at a reference voltage that is only slightly below the threshold voltage setting for the comparator to minimize integration time and increase sensitivity of the squelch. In this manner, a long time constant in the noise integrating filter can be used without having to wait for a long time to establish whether a carrier signal is present.

Abstract: A receiver squelch circuit has a programmable DC threshold level. The squelch circuit includes input circuitry that responds to an incoming signal by generating a decision signal when the DC voltage level of the incoming signal crosses a predetermined threshold level. A programmable control network selectively varies the predetermined threshold level.

Abstract: An FM audio signal receiver having a characteristic control function includes a receiving circuit for receiving an FM broadcast wave, a received state analyzing circuit for analyzing a state of the FM broadcast signal received by the receiving circuit, an analog-to-digital converter for analog-to-digital converting the FM broadcast signal received by the receiving circuit, a digital signal processor for performing processing for improving characteristics of the digital-to-analog converted signal, a parameter table memory for storing parameters for the digital signal processor and a control circuit for reading out a proper parameter for realizing improvement of a characteristic of the digital-to-analog converted signal from the parameter table memory in response to result of analysis by the received state analyzing circuit and controlling the digital signal processor with the read out parameter.

Abstract: A receiver (100) includes an audio section (200) which provides for compensated squelch settings which are automatically adjustable for changes in operating conditions such as changes in temperature or receiver channel spacing. Temperature circuit (128) provides a temperature signal (134) and controller (122) provides a signal indicating the channel spacing being used by receiver (100). The two signals are combined and formed into an address word which is in turn used to look-up a compensation word from memory location (218). The compensation word is then combined to a default squelch word by adder (216) providing for a compensated squelch word. The compensated squelch word automatically adjusts the squelch circuit's threshold level in order to compensate for changes in operational conditions affecting the squelch circuit.