CN106301640A - A kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique - Google Patents
A kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique Download PDFInfo
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- CN106301640A CN106301640A CN201610672674.5A CN201610672674A CN106301640A CN 106301640 A CN106301640 A CN 106301640A CN 201610672674 A CN201610672674 A CN 201610672674A CN 106301640 A CN106301640 A CN 106301640A
- Authority
- CN
- China
- Prior art keywords
- signal
- frequency
- road
- transmission method
- multichannel voice
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/09—Arrangements for device control with a direct linkage to broadcast information or to broadcast space-time; Arrangements for control of broadcast-related services
- H04H60/14—Arrangements for conditional access to broadcast information or to broadcast-related services
- H04H60/19—Arrangements for conditional access to broadcast information or to broadcast-related services on transmission of information
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/56—Arrangements characterised by components specially adapted for monitoring, identification or recognition covered by groups H04H60/29-H04H60/54
- H04H60/58—Arrangements characterised by components specially adapted for monitoring, identification or recognition covered by groups H04H60/29-H04H60/54 of audio
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/76—Television signal recording
- H04N5/91—Television signal processing therefor
- H04N5/92—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
- H04N5/926—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation
- H04N5/9265—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation with processing of the sound signal
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N7/00—Television systems
- H04N7/04—Systems for the transmission of one television signal, i.e. both picture and sound, by a single carrier
- H04N7/045—Systems for the transmission of one television signal, i.e. both picture and sound, by a single carrier the carrier being frequency modulated
Abstract
The present invention relates to data transmission and processing field, particularly relate to a kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique.This method comprises the following steps: A. multi-channel rf signal, including audio signal, broadcast singal, power supply signal, is mixed in a road transmission line；B. transmission line by mixing radio signal transmission to outlet terminal；C. outlet terminal branch export each road radiofrequency signal.The present invention realize by the way of analog-modulated is mixed MCVF multichannel voice frequency modulation and and power supply signal be mixed in a road transmission line and be transmitted, and be divided into many shunts by one and realize the cascade of terminal receiver, realize multicast, relaying is simple, power supply signal transmission line shares simultaneously, simplify cabling topology, it is to avoid digital data transmission needs multiply holding wire, relays the shortcomings such as numerous and diverse.
Description
Technical field
The present invention relates to data transmission and processing field, particularly relate to a kind of MCVF multichannel voice frequency based on FM modulation frequency mixing technique and pass
Transmission method.
Background technology
Standard EMUs transmit audio frequency and the broadcast singal of multichannel the most in high quality, be not exposed to definite transmission line and
The space of seat limits the effective transmission realizing one-to-many, and individual reception audio signal is the class received much concern in recent years
Topic.The most a lot of voices is that numeral encoding and decoding technique has the advantage of himself, but shortcoming is by numeral encoding and decoding network transmission
Digital junction volume is big, if using the transmission means of star topology, then for multipath reception, outlet is too much, relaying
Volume ratio is bigger；If using the transmission means of daisy topology, the problem brought is that relaying is too much, and each relaying needs individually
Power supply, and the realization relayed complexity for simulation shunt is much higher, and cost also can be much higher.
Summary of the invention
The present invention provides a kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique, is mixed by analog-modulated
Mode realize MCVF multichannel voice frequency modulation and and power supply signal be mixed in a road transmission line and be transmitted, and be divided into many branches by one
Device realizes the cascade of terminal receiver.
The present invention is achieved in that a kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique, including following
Step:
A. multi-channel rf signal, including audio signal, broadcast singal, power supply signal, is mixed in a road transmission line；
B. transmission line by mixing radio signal transmission to outlet terminal；
C. outlet terminal branch export each road radiofrequency signal.
As a further improvement on the present invention, described step A includes:
A1. choose frequency range carrier wave audio signal or broadcast singal are modulated respectively；
A2. audio signal or broadcast singal after modulating every road add new local oscillation signal and are mixed, filter, and obtain carrier wave
The FM signal of frequency；
A3. multipath audio signal or broadcast singal are amplified, carry out secondary filtering, filled to radio-frequency transmissions by blender mixing
Put, obtain hybrid radio frequency signal, and transmit through same transmission line.
RF signal application local oscillation signal after modulation is mixed, it is to avoid a large amount of spuious dispersion of radiofrequency signal is too
Greatly, spuious scope is controlled, it is simple to wave filter filters.
As a further improvement on the present invention, described hybrid radio frequency signal is in RF transmitter after superposition 12V voltage
Output.
As a further improvement on the present invention, described local oscillation signal is divided into each road originally via crystal oscillator by shunt
Vibration frequency, then local frequency amplification, filtering are obtained.Local oscillation signal is shunted to each road local oscillation signal, Shi Ge road radiofrequency signal
When adding local oscillation signal, the interference between local oscillation signal will not occur.
As a further improvement on the present invention, described each road broadcast singal is divided into by shunt by total broadcast singal, institute
State broadcast singal to be preferentially modulated playing.Broadcast audio has the highest priority, when there being broadcast singal interim, all of
Passage is required for being switched to the broadcasting of broadcasting speech, so end is just divided into broadcast singal and audio signal when processing before modulation
Two parts, when there being broadcast singal interim, all of modulation channels is all switched to broadcast audio and is modulated.So connect in terminal
Receiving device, no matter which passage who passenger listens at, receives when there being broadcasting speech all can be switched to broadcasting speech temporarily
Listen.
As a further improvement on the present invention, the modulation transmissions frequency of described transmission line is 40MHZ-45 MHZ.
As a further improvement on the present invention, described step C also includes:
C1. outlet terminal receives hybrid radio frequency signal, and hybrid radio frequency signal is carried out branch；
C2. after branch, main road radio frequency signal attenuation the first voltage is to next road outlet terminal, from road radio frequency signal attenuation the second electricity
It is pressed onto seat receptor.
Before radio signal transmission to terminal, need the difference according to receiving terminal to be divided into different transmission branches, and decline
It is kept to different voltage, to adapt to the transmission needs of each branch road.
As a further improvement on the present invention, described first voltage attenuation is 0.8 ± 0.1dB.
As a further improvement on the present invention, described second voltage attenuation is 40 ± 8dB.
As a further improvement on the present invention, described step C also includes:
C3. seat receptor receives radiofrequency signal, by high Q value inductance separation power supply signal and audio radio-frequency signal, enters back into
Filtering, radiofrequency signal and local oscillation signal after filtering are mixed through frequency mixer jointly, export a standard FM broadcast frequency
Rate signal, again passes by wave filter to demodulator, is demodulated into audio signal output and plays, passenger can according to oneself need select
Different audio frequency is play.
The invention has the beneficial effects as follows: the present invention realizes MCVF multichannel voice frequency modulation and electricity by the way of analog-modulated is mixed
Source signal is mixed in a road transmission line and is transmitted, and is divided into many shunts by one and realizes the cascade of terminal receiver, real
Existing multicast, relaying is simple, and power supply signal transmission line shares simultaneously, simplifies cabling topology, it is to avoid digital data transmission needs
Want multiply holding wire, relay the shortcomings such as numerous and diverse.
Accompanying drawing explanation
Fig. 1 is the flow chart of the broadcast singal branch that the present invention provides；
Fig. 2 is the flow chart of the local oscillation signal branch that the present invention provides;
Fig. 3 is the flow chart of the radiofrequency signal mixing that the present invention provides；
Fig. 4 is the flow chart of the radiofrequency signal output that the present invention provides；
Fig. 5 is the voice-operated flow chart of radiofrequency signal that the present invention provides；
Fig. 6 is the flow chart of the radiofrequency signal terminal output that the present invention provides.
Detailed description of the invention
In order to make the purpose of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, right
The present invention is further elaborated.
As shown in Figures 1 to 6, the present invention provides a kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique, bag
Include following steps:
A. multi-channel rf signal, including audio signal, broadcast singal, power supply signal, is mixed in a road transmission line；
B. transmission line by mixing radio signal transmission to outlet terminal；
C. outlet terminal branch export each road radiofrequency signal.
As a kind of embodiment of the present invention, step A therein includes:
A1. choose frequency range carrier wave audio signal or broadcast singal are modulated respectively；
A2. audio signal or broadcast singal after modulating every road add new local oscillation signal and are mixed, filter, and obtain carrier wave
The FM signal of frequency；
A3. multipath audio signal or broadcast singal are amplified, carry out secondary filtering, filled to radio-frequency transmissions by blender mixing
Put, obtain hybrid radio frequency signal, and transmit through same transmission line.
As a kind of embodiment of the present invention, hybrid radio frequency signal exports after superposition 12V voltage in RF transmitter.
As a kind of embodiment of the present invention, each road local oscillation signal is divided into each road local oscillator by crystal oscillator by shunt
Frequency, then local frequency amplification, filtering are obtained.
As a kind of embodiment of the present invention, each road broadcast singal is divided into by shunt by total broadcast singal, described extensively
Broadcast signal priority to be modulated playing.
As a kind of embodiment of the present invention, the modulation transmissions frequency of transmission line is 40MHZ-45 MHZ.The most
Road is 40.8MHZ, 41.9MHZ, 42.8MHZ, 44.3MHZ, 43.6MHZ respectively.
As a kind of embodiment of the present invention, step C also includes:
C1. outlet terminal receives hybrid radio frequency signal, and hybrid radio frequency signal is carried out branch；
C2. after branch, main road radio frequency signal attenuation the first voltage is to next road outlet terminal, from road radio frequency signal attenuation the second electricity
It is pressed onto seat receptor.Wherein the first voltage attenuation is 0.8 ± 0.1dB, and the second voltage attenuation is 40 ± 8dB.
As a kind of embodiment of the present invention, step C also includes:
C3. seat receptor receives radiofrequency signal, by high Q value inductance separation power supply signal and audio radio-frequency signal, enters back into
Filtering, radiofrequency signal and local oscillation signal after filtering are mixed through frequency mixer jointly, export a standard FM broadcast frequency
Rate signal, again passes by wave filter to demodulator, is demodulated into audio signal output and plays.
The present invention proposes a kind of energy and is suitable for audio speech modulation transmissions and the method for mixing reception broadcasting of standard EMUs,
The method requires that modulation transmissions frequency is about 40MHZ, avoids standard FM radio band limits, requires that framework is simple simultaneously,
Reliability is high.
The technical scheme is that
1) according to judging to broadcast the level of enable pin, through analog switch switching MCVF multichannel voice frequency and broadcasting speech；
2) use suitable frequency range carrier wave that MCVF multichannel voice frequency is modulated respectively；
3) radiofrequency signal after modulating every road adds new local oscillation signal and is mixed, and filtering obtains required carrier frequency
The FM signal of rate；
4) signal after multichannel modulation mixing, after filtering, amplifies, after secondary filtering, utilizes blender to carry out mixing to penetrating
Frequently launch-box；
5) the mixed audio signal of multichannel exports after radio-frequency transmissions box superposition 12V power supply；
6) signal handled well entertains control unit by coaxial cable transmission to audio frequency, and main road decay 0.8 ± 0.1dB is to next
Road amusement control unit, the 40 ± 8dB that decays respectively from road is to seat receptor；
7) seat receptor receives radiofrequency signal, by high Q value inductance separation power supply signal and audio radio-frequency signal, enters back into filter
Ripple, signal and local oscillator signal out after filtering be mixed through frequency mixer jointly, and outputting standard FM broadcasting frequency is again
Secondary device after filtering, to demodulator, is demodulated into audio signal output and plays；
One embodiment of the present invention FB(flow block): modulate mixing transmission, process of both mixing demodulation reception.
1) implementation of modulation mixing transmission:
Five road audio frequency are modulated to FM signal, passage 1,2,3,4,5 and local oscillator by manipulator and carrier wave sinusoidal clock frequency 1-5
Signal 1-5 is mixed respectively through frequency mixer, and cross band-pass filter obtaining carrier frequency is five road different frequency radiofrequency signals；
Signal after modulation mixing and filtering amplifies respectively through power amplifier again, and secondary filtering Hou five road signal mixes through blender
Closing, synthesize the one-channel signal of a road multiple frequency components, the one-channel signal of this multiple frequency components needs to enter radio frequency output board (i.e. frame
Interconnecting device described in figure) it is superimposed with 12V power supply and is divided into two-way to pass through coaxial cable output transmission.
This process be i.e. modulate, be mixed, filter, amplify, the mixing of secondary filtering, multichannel, power supply superposition, the mistake of branch output
Journey.
2) implementation that mixing demodulation receives:
One point three is realized through audio frequency control box (shunt), main road coupling attenuation with superposition power supply duplex audio modulation signal
0.8 ± 0.1dB, to next road audio frequency control box, respectively decays 40 ± 8dB to seat receptor from road through one-to-two branch.
Enter seat receptor signal, be mixed, filtering, then be demodulated to demodulation chip, finally obtain audio frequency letter
Number, play by earphone speaker and channel is play in seven segment digital tubes display.
This process is i.e. the process that power supply signal separates, is mixed, filters, demodulates, audio frequency is play.
Owing to being that mixed transport is modulated and be mixed to multi-channel audio in this programme, and it is mixed demodulation and receives, modulate and mix
Can produce substantial amounts of spuious during Pin, five road-load wave frequencies are separated by relatively near, filter the most important, prevent spuious mixing
Receiving terminal causes reception interference.
Modulation mixing mixed transport and again mixing demodulation reception are complete processes, owing to criteria of right and wrong FM receives and dispatches sound
The frequency band range of frequency modulation, can be effectively prevented from standard FM radio frequency and disturb it, has multicast, and relaying is simple,
Power supply signal transmission line shares, and simplifies cabling topology, it is to avoid digital data transmission needs multiply holding wire, relays numerous and diverse grade and lacks
Point.
Efficiently solve the problem that EMUs space little for entertainment audio, broadcast audio transmission and seat receives.
Above content is to combine concrete preferred implementation further description made for the present invention, it is impossible to assert
Being embodied as of the present invention is confined to these explanations.For general technical staff of the technical field of the invention,
On the premise of present inventive concept, it is also possible to make some simple deduction or replace, all should be considered as belonging to the present invention's
Protection domain.
Claims (10)
1. a MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique, it is characterised in that comprise the following steps:
A. multi-channel rf signal, including audio signal, broadcast singal, power supply signal, is mixed in a road transmission line；
B. transmission line by mixing radio signal transmission to outlet terminal；
C. outlet terminal branch export each road radiofrequency signal.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 1, it is characterised in that described step
Rapid A includes:
A1. choose frequency range carrier wave audio signal or broadcast singal are modulated respectively；
A2. audio signal or broadcast singal after modulating every road add new local oscillation signal and are mixed, filter, and obtain carrier wave
The FM signal of frequency；
A3. multipath audio signal or broadcast singal are amplified, carry out secondary filtering, filled to radio-frequency transmissions by blender mixing
Put, obtain hybrid radio frequency signal, and transmit through same transmission line.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 2, it is characterised in that described mixed
Close radiofrequency signal to export after superposition 12V voltage in RF transmitter.
The most according to claim 2 based on FM modulation frequency mixing technique MCVF multichannel voice frequency transmission method, it is characterised in that described respectively
Road local oscillation signal is divided into each road local frequency by crystal oscillator by shunt, then obtains local frequency amplification, filtering.
The most according to claim 2 based on FM modulation frequency mixing technique MCVF multichannel voice frequency transmission method, it is characterised in that described respectively
Road broadcast singal is divided into by shunt by total broadcast singal, and described broadcast singal is preferentially modulated playing.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 1, it is characterised in that described biography
The modulation transmissions frequency of lines is 40MHZ-45MHZ.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 1, it is characterised in that described step
Rapid C also includes:
C1. outlet terminal receives hybrid radio frequency signal, and hybrid radio frequency signal is carried out branch；
C2. after branch, main road radio frequency signal attenuation the first voltage is to next road outlet terminal, from road radio frequency signal attenuation the second electricity
It is pressed onto seat receptor.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 7, it is characterised in that described the
One voltage attenuation is 0.8 ± 0.1dB.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 7, it is characterised in that described the
Two voltage attenuations are 40 ± 8dB.
MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique the most according to claim 7, it is characterised in that described
Step C also includes:
C3. seat receptor receives radiofrequency signal, by high Q value inductance separation power supply signal and audio radio-frequency signal, enters back into
Filtering, radiofrequency signal and local oscillation signal after filtering are mixed through frequency mixer jointly, export a standard FM broadcast frequency
Rate signal, again passes by wave filter to demodulator, is demodulated into audio signal output and plays.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610672674.5A CN106301640A (en) | 2016-08-16 | 2016-08-16 | A kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610672674.5A CN106301640A (en) | 2016-08-16 | 2016-08-16 | A kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique |
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Family
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| CN201610672674.5A Pending CN106301640A (en) | 2016-08-16 | 2016-08-16 | A kind of MCVF multichannel voice frequency transmission method based on FM modulation frequency mixing technique |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107302375A (en) * | 2017-06-21 | 2017-10-27 | 苏州华启智能科技有限公司 | A kind of audio FM modulation circuits |
| CN109327664A (en) * | 2018-12-21 | 2019-02-12 | 北京淳中科技股份有限公司 | Signal processing method, signal output and input unit, display panel control and system |
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| CN105657509A (en) * | 2016-01-26 | 2016-06-08 | 泰斗微电子科技有限公司 | LNB (Low Noise Amplifier) module for receiving satellite television signal and corresponding satellite television set top box |
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| CN2775939Y (en) * | 2004-12-23 | 2006-04-26 | 北京东方信联科技有限公司 | Frequency selector for direct sending station of mobile communication |
| CN101459434A (en) * | 2007-12-10 | 2009-06-17 | 杨林 | Remote control device for constant voltage addressable broadcast system |
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| CN107302375A (en) * | 2017-06-21 | 2017-10-27 | 苏州华启智能科技有限公司 | A kind of audio FM modulation circuits |
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Application publication date: 20170104 |