31 results about "FM transmitter" patented technology

A portable handheld digital content player has an integrated wireless interface, an integrated FM transmitter and an integrated auto on and auto off feature for ease of use in vehicles. The player and associated software on a base content server provide automated broadband wireless content downloads to the player while in a vehicle and transfer of audio to the vehicle stereo via FM band transmission without the use of an accessory. The player integrates an FM scan function to search for a suitable frequency for transmitting within the FM band. The player integrates some PDA-like functionality including personal contact information, appointment calendar, user schedule, email in addition to others.

The invention discloses a high-efficiency frequency modulation transmitter, which relates to a transmitting device in the wireless monitoring and control communication technology and comprises a frequency modulation source, a power amplifier, an isolator, a power supply circuit, an antenna and a premodulation filter, wherein the premodulation filter is used for filter processing on PCM (Pulse Code Modulation) signals that are input; the premodulation filter is connected with the frequency modulation source; the power amplifier is a switching power amplifier; the switching power amplifier selects a GaAs device or a GaN device; the grid voltage of the GaAs device or the GaN device is negative electricity offset; the power supply circuit is a power supply and time-sequence control circuit; and the GaAs device or the GaN device is matched with power supply time-sequence. The high-efficiency frequency modulation transmitter reduces power consumption of the transmitter, reduces the heat dissipation requirement of the transmitter, and facilitates the integration and the miniaturization of the transmitter.

An FM transmitter which can be easily connected to an existing computer or the like and does not need any troublesome operation is provided. An FM transmitter 100 has an USB device function which can be connected to a PC 400 as an USB host device and comprises a power supply circuit130 which is connected to the power supply pin of an USB socket 410 to generate a predetermined operating voltage when an USB plug 110 is connected to the USB socket 410 of the PC 400, an USB controller 120 for requesting that its own apparatus being a device audio source inputs/outputs data by isochronous transfer in a configuration performed by the PC 400 and a transmission processing section 140 which is actuated by the operating voltage supplied by the power supply circuit 130 and applies FM-modulation to audio data outputted from the PC 400 via the USB socket 410 for transmission.

A wireless audio transmission/reception system is provided. The transmission/reception system includes an FM detector for detecting an occupied channel among radio FM channels, a microprocessor for selecting a using channel that is greatly different in frequency from the detected occupied channel and thus does not interfere therewith, an FM transmitter built in an audio replay system to transmit/receive an audio signal over the using channel, and an external audio system for receiving and outputting the audio signal from the FM transmitter.

The invention relates to the field of digital frequency modulation receivers, and particularly relates to a 433M digital frequency modulation receiver, which comprises a low-noise amplifier and a 433M filter part at the input end, a 392.3M local oscillator source signal circuit part, a frequency mixer and an intermediate frequency filter part, a demodulation secondary frequency reduction circuit part, a single chip micro processing part, and a power control and ground part for the entire circuit diagram. The 433M digital frequency modulation receiver provided by the invention has the advantages that the design is clever; the layout is reasonable; the power consumption is low; the sensitivity is high; the dynamic range is large; and by adopting a 2FSK modulation and demodulation mode, real-time communication with a 433M digital frequency modulation transmitter can be well carried out. The 433M digital frequency modulation receiver has a high scientific research value in the ultra-short wave communication field and has a certain project application value.

The invention provides a wireless transmitting system and an achievement method of the wireless transmitting system. The wireless transmitting system comprises a tour guide instrument and a tourist tour guide instrument. The tour guide instrument is internally composed of a frequency modulation transmitter and an FM grouping device. The FM grouping device internally comprises a wireless communication module and used for transmitting a compulsively-set frequency signal to the tourist tour guide instrument through the wireless communication module. The tourist tour guide instrument is internally composed of a frequency modulation receiver and a wireless communication module. The wireless communication module in the tourist tour guide instrument is used for receiving the compulsively-set frequency signal transmitted from the FM grouping device to set the corresponding frequency of the frequency modulation receiver. According to the wireless transmitting system and the achievement method, the FM grouping device is additionally arranged in the frequency modulation transmitter used by a tour guide, when the frequency modulation receiver can not receive the signal of the frequency modulation transmitter, the frequency of the frequency modulation transmitter is broadcasted regularly through the wireless communication modules, the frequency of the frequency modulation receiver can be automatically or manually changed, and a tourist can receive the new signal of the frequency modulation transmitter of the tour guide and hear explanations of the tour guide.

An optoelectronic pickup that generates a fluctuating voltage that is analogous to the vibrations of a vibrating body. When utilized with the vibrating body of a musical instrument and amplified and fed to a speaker the musical tones are reproduced at an amplified level. When the signal is fed to an FM transmitter the musical tones can be reproduced in any FM radio receiver. The device makes possible portable electric instruments and "wireless'-electrical instruments, i.e. a guitar that does not require a connecting cord or amplifier. The device anticipates new and unique musical instruments.

The invention discloses a frequency modulation transmitter device based on Bluetooth communication. The mobile phone comprises a built-in Bluetooth communication transceiving module of the mobile phone, the invention discloses an HC-05 Bluetooth communication transceiver module. The invention discloses an STC89C52 single-chip microcomputer signal processing circuit. Power supply electronic switchcontrol circuit, third-stage power amplifier, the system comprises a final-stage power amplifier, a first-stage power amplifier, a second-stage power amplifier, an automatic gain AGC control circuit,a delay AGC control circuit, an MIC audio amplifier or external audio signal, a voltage-controlled oscillation and frequency modulation circuit, an OP07 active amplification circuit, an MC145152-2 frequency division and phase discrimination circuit and an MC12022AP prescaler, wherein the MIC audio amplifier or the external audio signal outputs a signal to the voltage-controlled oscillation and frequency modulation circuit; the voltage-controlled oscillation and frequency modulation circuit outputs signals to the MC12022AP prescaler and the first-stage power amplifier; and the MC12022AP prescaler outputs a signal to the MC145152-2 frequency division and phase discrimination circuit.

The invention discloses a terminal FM function testing device, method and system. The testing device comprises a shielding space, a testing host, a tested terminal, an earphone antenna and a pluralityof FM transmitters. The testing host, a tested terminal, an earphone antenna and a plurality of FM transmitters are all arranged in the shielding space, wherein the tested terminal and the FM transmitters are electrically connected with the testing host, and the earphone antenna is electrically connected with the tested terminal; each FM transmitter is used for transmitting FM signals; the testedterminal is used for receiving the FM signals; and the testing host is used for setting emission parameters of the plurality of FM emitters according to the testing case, controlling the tested terminal to search FM signals and/or switch channels of the currently received the FM signals, and detecting an FM function of the tested terminal according to the test case and FM information of the FM signals received by the tested terminal. According to the invention, automatic test of channel searching and channel switching functions in the FM function of the terminal can be realized, so that the test of the FM function of the terminal is enriched.

The invention provides an eight-channel frequency modulation transmitting all-in-one machine, which comprises a case, and is characterized in that eight input ports, a decoding unit, an eight-channeladjusting plate, a synthesizer, a power amplifier, a power supply, a switch, a video interface and an antenna interface are arranged in the case; the decoding unit comprises an audio decoder group andan audio-video decoder; the input ports are connected with the audio decoder group or the audio-video decoder, the audio decoder group or the audio-video decoder is respectively connected with the eight-channel adjusting plate, the eight-channel adjusting plate integrates the eight-channel FM modulator and the eight-path radio frequency device; the eight-channel adjusting plate is externally connected with the synthesizer; the synthesizer is connected with the power amplifier; the power amplifier is connected with the antenna interface; and the audio and video decoder decodes the audio part,and the video part is directly output to the video interface. The eight-channel frequency modulation transmitting all-in-one machine is reasonable in structural design, and compared with a traditionalfrequency modulation transmitter, the all-in-one machine integrates eight channels in one case, so that audio/audio/video information of the eight channels can be received, processed and sent at thesame time, energy consumption is reduced, energy is saved, and the environment is protected.

The invention relates to a frequency modulation transmitter and electronic equipment, and relates to the technical field of communication. The frequency modulation transmitter comprises: a modulation circuit which comprises a signal acquisition unit and a signal generation unit, wherein the signal acquisition unit is used for acquiring an analog signal, and the signal generation unit is used for generating a bias voltage and superposing the bias voltage and the analog signal to output an analog modulation signal; an oscillation circuit which comprises a first capacitor and a tunnel diode, wherein the first capacitor and the tunnel diode are used for forming an oscillation loop, and the oscillation loop is used for accessing an analog modulation signal and converting the analog modulation signal into a radio frequency carrier signal; and an antenna which is coupled to the oscillation circuit and is used for transmitting the radio frequency carrier signal. The power consumption of the frequency modulation transmitter can be reduced to a micro-watt level.

The invention provides a device for wirelessly detecting abnormal sound of a vehicle, and the device comprises a piezoelectric ceramic sensor which converts the received vibration into an electric signal; a clamping component installed on any part, suspected to have abnormal sound, of the vehicle, wherein the piezoelectric ceramic sensor is arranged in the clamping component; a FM transmitter used for receiving the electric signal and amplifying the electric signal, wherein the FM transmitter outputs the amplified electric signal as an audio signal, and the FM transmitter is fixed on the clamping part; and a vehicle-mounted radio used for receiving the audio signal and judging the part where the abnormal sound is located according to the frequency corresponding to the abnormal sound of the vehicle-mounted radio. The problem that an existing wired detection device needs to pull a lot of long wires into a cab and is unsafe is solved. Meanwhile, the problem of misjudgment caused by the fact that various abnormal sounds exist at the same time and the abnormal sounds fed back by a maintainer and a vehicle owner are not from the same source due to the fact that the used earphone is operated by a single person is solved.

This invention provides an automatic controlled FM transmitting device including a FM transmitter and an outer host, in which, a slave control part is connected with the outer host, the FM transmitter includes a slave controller, a FM modulator and an emission antenna, the input of the slave controller is connected with a primary controller, the output of the slave controller is connected with the FM modulator, the output of the FM modulator is connected to the emission antenna. A method includes: the slave controller judges if there is sound source input from the exterior host, if there is sound source input, the supply of the FM modulator is turned on to supply to the FM modulator to emit modulation carrier signals, when there is not sound source input, the supply is cut off after timing a period of time to shut the emitter and stop the emission of FM carrier signals.

The invention discloses a method for outputting two paths of independent sound sources based on an Android system. The method comprises the following steps: S1, sending an original audio in a system to a Codec audio device of a main controller for decoding by using an Android system original audio stream type, outputting the decoded original audio to an audio amplifier through a line out interface, and finally outputting the decoded original audio through a loudspeaker of the intelligent rearview mirror; and S2, sending the original audio in the system to newly added virtual Codec audio equipment for decoding by expanding an audio strategy and using the expanded audio data of one Android audio stream type, and outputting the audio data to an FM transmitter through an I2S interface. The method has the advantages that the control logic of the sound output path of the native Android system is modified, the double channels of the horn and the FM emitter are supported on hardware, two independent sound source outputs are achieved, the two sound outputs are independent of each other, and the sound content is different. Receiving of other sound information such as navigation is not affected when music is experienced, the two sound sources are different, auditory lag cannot be caused, meanwhile, the volumes of the two sounds are independently controlled and can be freely set, and the volume of the other sound source cannot be affected during broadcasting.

The invention relates to the technical field of emergency broadcast debugging, in particular to an emergency broadcast RDS modulation degree test method and system. The method is applied to an RDS modulation degree test system. The system comprises an emergency broadcast adapter and an FM transmitter. The method comprises the following steps: receiving an antenna signal transmitted by an FM transmitter, and extracting a pilot signal in the antenna signal; processing the antenna signal, outputting a baseband signal, and extracting an RDS signal from the baseband signal; collecting the amplified pilot signal and the amplified RDS signal, performing analog-to-digital conversion, and calculating the amplitude of the RDS signal relative to the pilot signal according to conversion data; and adjusting the modulation degree of the RDS signal according to the difference between the amplitude of the RDS signal relative to the pilot signal and the empirical value. According to the invention, the intensity of the RDS signal can be accurately read out, an engineering constructor can accurately adjust the FM transmitter through the assistance of a village-equipped adapter, the debugging process is simple and convenient, a special frequency spectrograph is not needed, the cost is low, and the debugging difficulty of the emergency broadcast is reduced.