CN202586958U - Frequency modulation handheld station provided with automatic power control - Google Patents

Abstract

The utility model relates to the technical field of walkie-talkies, and provides a frequency modulation hand-held station with automatic power control, which has reasonable structure, good communication effect, long continuous working time, convenient portability and stable output power. Composed of internal circuits and electronic components, the circuit includes an antenna, a bandpass filter, a transmitting/receiving switch, a receiving amplifier, a transceiver FM module, a baseband processor, a central processing unit, a phase-locked loop, an audio modulation module, a microphone, Receive audio amplifier, speaker, buffer amplifier, transmit power amplifier and automatic power control module.

Description

An FM handheld station with automatic power control

technical field

The utility model relates to the technical field of walkie-talkies, in particular to a frequency modulation handheld station with automatic power control.

Background technique

With the continuous development of radio technology, radio stations, as a relatively mature half-duplex voice communication system, have been widely used in various fields such as public security, fire protection, hotels, shopping malls and restaurants, but there are generally many shortcomings in existing radio stations. Disadvantages: Generally, they work in the 450MHz frequency band. Since the 450MHz frequency band is a license-free frequency band, the stations working in this frequency band will inevitably be interfered by other stations using the same frequency. The output power is unstable and the communication effect is poor. ; At the same time, due to the low frequency of the 450MHz frequency band, the volume and weight of traditional radio stations are usually large, which is not easy to carry; It is relatively large. Generally, if the battery capacity is large, the volume and weight will also become larger, which is not easy to carry. If the volume is considered, the continuous working time will be short, which cannot meet the needs of users.

Contents of the invention

Therefore, in view of the above problems, the utility model proposes a FM hand-held station with automatic power control with reasonable structure, good communication effect, long continuous working time, easy to carry, and stable output power.

In order to solve this technical problem, the utility model adopts the following scheme: a FM handheld station with automatic power control, which is composed of a hand-held housing, a circuit and electronic components arranged in the hand-held housing, and the circuit includes an antenna, a band pass Filter, transmit/receive switch, receive high amplifier, transceiver FM module, baseband processor, central processing unit, phase-locked loop, audio modulation module, microphone, receive audio amplifier, loudspeaker, buffer amplifier and transmit power amplifier, including automatic Power control module, the antenna is connected to the transmitting/receiving switch through a bandpass filter, the input of the transmitting/receiving switch is connected to the transmitting power amplifier, the output is connected to the receiving high amplifier, and the output of the receiving high amplifier is connected to the transceiver FM module , the transceiver frequency modulation module is also connected with the baseband processor, central processing unit, phase-locked loop and buffer amplifier respectively, and the central processing unit is also connected with the phase-locked loop and automatic power control module, and the automatic power control module It is connected with the transmission power amplifier, the phase-locked loop is also connected with the baseband processor, the buffer amplification output is connected with the transmission power amplifier, and the baseband processor is also connected with the audio modulation module and the receiving audio amplifier respectively, and the audio frequency The modulation module is connected with the microphone, and the output of the receiving audio amplifier is connected with the speaker.

Further, the output of the phase-locked loop is connected to an out-of-lock detector, and the output of the out-of-lock detector is connected to the central processing unit.

Further, a squelch circuit is provided between the receiving audio amplifier and the speaker, and the squelch circuit is also connected to the central processing unit.

Further, the central processing unit is also connected to a standby mode switch.

By adopting the aforementioned technical scheme, the beneficial effects of the utility model are: an automatic power control is set on the output of the power transmission, which ensures the stability of the output power, and an out-of-lock detector is set so that the utility model is in the phase-locked loop out-of-lock and empty channel The detection will automatically send an alarm function, and when it is not in use, it will directly enter the standby mode, effectively reducing power consumption; the utility model has the advantages of good communication effect, long continuous working time, convenient carrying, stable output, etc., and can be widely used in Industrial and commercial, transportation, railway, petrochemical, forestry, property management, construction, marine fishery and other industries.

Description of drawings

Fig. 1 is a system block diagram of the utility model embodiment.

Detailed ways

The utility model is further described now in conjunction with accompanying drawing and specific embodiment.

Referring to Fig. 1, a preferred FM hand-held station with automatic power control of the utility model is composed of a hand-held housing and a circuit and electronic components arranged in the hand-held housing, the circuit includes an antenna 1, a band-pass filter 2. Transmitting/receiving switch 3, receiving high amplifier 4, transceiver FM module 5, baseband processor 6, central processing unit 7, phase-locked loop 8, audio modulation module 9, microphone 10, receiving audio amplifier 11, speaker 12, buffer Amplifying 13, transmitting power amplifying 14, automatic power control module 15, out-of-lock detector 16, squelch circuit 17 and standby mode switch 18, described antenna 1 is connected with transmitting/receiving switch 3 through band-pass filter 2, so The input of the transmitting/receiving switch 3 is connected to the transmitting power amplifier 14, and the output is connected to the receiving high amplifier 4, and the output of the receiving high amplifier 4 is connected to the transceiver frequency modulation module 5, and the transceiver frequency modulation module 5 is also connected to the baseband processor 6, the central Processor 7, phase-locked loop 8 and buffer amplifier 13 are connected, and described central processing unit 7 is also connected with phase-locked loop 8, automatic power control module 15 and standby mode switch 18, and described automatic power control module 15 is connected with transmitting The power amplifier 14 is connected, the phase-locked loop 8 is also connected to the baseband processor 6, the output of the buffer amplifier 13 is connected to the transmit power amplifier 14, and the baseband processor 6 is also connected to the audio modulation module 9 and the receiving audio amplifier 11 respectively The audio modulation module 9 is connected with the microphone 10, and the output of the receiving audio amplifier 11 is connected with the loudspeaker 12 through the squelch circuit 17, and the squelch circuit 17 is also connected with the central processing unit 7, and the lock The output of the phase loop 8 is also connected to an out-of-lock detector 16 , and the output of the out-of-lock detector 16 is connected to the central processing unit 7 .

The working principle of the utility model: it is composed of a transmitting circuit and a receiving circuit. The transmitting circuit is converted into an electrical signal through the audio modulation module 9 by inputting the voice signal of the microphone 10, and then amplifying, companding, scrambling, and pre-amplifying through the baseband processor 6. Emphasis, limiting and filtering, then input to the transceiver FM module 6 to modulate the output radio frequency signal, then through buffer amplification 13 and transmission power amplification 14, and the automatic power control module 15 automatically detects the size of the output power, if the power is too large, then Output a control voltage to reduce the output power, on the contrary, to increase the output power, and then transmit/receive switch 3 through the band-pass filter 2 and transmit it from the antenna 1; the receiving circuit adopts the double frequency conversion superheterodyne method, by Antenna 1 receives a weak signal, input it to bandpass filter 2, and then output it to receiving high amplifier 4 through transmit/receive switch 3, and then the radio frequency amplified signal enters the first mixer in the transceiver FM module 5, where the first mixer In the device, the RF amplified signal from the receiving amplifier 4 is mixed with the first local oscillator signal from the phase-locked loop 8 to generate a first intermediate frequency signal, and the first intermediate frequency signal is further eliminated by a 46.35MHZ crystal filter. The clutter signal, the filtered first intermediate frequency signal enters the second mixer, and is mixed again with the 45.9MHZ second local oscillator signal obtained by triple frequency of the reference crystal oscillator to generate the second intermediate frequency signal, and the second intermediate frequency signal passes through After the two ceramic filters filter out unwanted stray signals, they are amplified and discriminated against to complete the frequency selection amplification, frequency mixing and demodulation of the transceiver FM module 4 to generate audio signals and signaling coded signals, wherein the audio signals are processed by baseband Processed by the device 6, it enters the receiving audio amplifier to amplify and drive the speaker, while the CTCSS and DCS signaling coded signals are sent to the central processing unit 7 for decoding and identification, and a part of the audio signal is detected and rectified by the filter and amplifier to generate a noise component The DC voltage corresponding to the noise component is sent to the analog port of the above-mentioned central processing unit 7 and compared with the preset voltage value, and the opening or closing output of the speaker is controlled by the squelch circuit 17 connected according to the comparison result; wherein the phase lock Also connect an out-of-lock detector 16 on the ring 8, if phase-locked loop 8 out-of-lock, then send a low-level signal to central processing unit 7 through the out-of-lock detector 16, after central processing unit 7 receives the out-of-lock signal, Close the transmission channel, the transmitter stops working, and when not in use, the handheld station is entered into the standby mode by the standby mode switch 18, so as to save its power consumption.

The utility model ensures the stability of the output power by setting an automatic power control on the power transmission output, and setting an out-of-lock detector makes the utility model automatically send an alarm function when the phase-locked loop is out of lock and the detection of an empty channel is not needed. When in use, it directly enters the standby mode, effectively reducing power consumption; the utility model has the advantages of good communication effect, long continuous working time, convenient carrying, stable output, etc., and can be widely used in industry, commerce, transportation, railways, petrochemicals, Forestry, property management, construction, marine fishery and other industries.

Although the utility model has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that, without departing from the spirit and scope of the utility model defined by the appended claims, changes in form and details may be made. Making various changes to the utility model is within the protection scope of the utility model.

Claims (4)

1. the frequency modulation hand-held station of a band automated power control; Form by hand-hold type shell and the circuit and the electronic component that are arranged in the hand-hold type shell; Said circuit comprises that frequency modulation module, BBP, central processing unit, phase-locked loop, voice modulation module, microphone, reception audio frequency amplifier, loud speaker are put, received and dispatched to antenna, band pass filter, transmit/receive switch, reception height, buffering is amplified and transmitting power is amplified; It is characterized in that: also comprise automatic power control module, said antenna is connected with transmit/receive switch through band pass filter, and said transmit/receive switch input is connected in transmitting power and amplifies; Output is connected in the reception height and puts; Said reception height is put output and is connected transmitting-receiving frequency modulation module, and said transmitting-receiving frequency modulation module also is connected with BBP, central processing unit, phase-locked loop and buffering amplification respectively, and said central processing unit also is connected with automatic power control module with phase-locked loop; Said automatic power control module is connected with the transmitting power amplification; Said phase-locked loop also is connected in BBP, and said buffering is amplified output and connected the transmitting power amplification, and said BBP also is connected with the reception audio frequency amplifier with the voice modulation module respectively; Said voice modulation module is connected with microphone, and said reception audio frequency amplifier output connects loud speaker.

2. the frequency modulation hand-held station of band automated power control according to claim 1 is characterized in that: said phase-locked loop output connects an out-of-lock detector, and this out-of-lock detector output connects central processing unit.

3. the frequency modulation hand-held station of band automated power control according to claim 1, it is characterized in that: be provided with squelch circuit between said reception audio frequency amplifier and the loud speaker, this squelch circuit also is connected with central processing unit.

4. the frequency modulation hand-held station of band automated power control according to claim 1, it is characterized in that: said central processing unit also connects a standby mode switch.