CN1251961A - VLF ground wave telephone equipment - Google Patents
VLF ground wave telephone equipment Download PDFInfo
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- CN1251961A CN1251961A CN98121809A CN98121809A CN1251961A CN 1251961 A CN1251961 A CN 1251961A CN 98121809 A CN98121809 A CN 98121809A CN 98121809 A CN98121809 A CN 98121809A CN 1251961 A CN1251961 A CN 1251961A
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Abstract
A VLF ground wave telephone equipment in VLF band (20-300 KHz) is composed of user extensions, switch, ground wave telephone power amplifier-transmitter, ground coupled transmitting network and power supply. Said user extensions consist of emitter, receiver and dialing circuit. Said ground coupled transmitting network is composed of feed back line, impedance converter, transmitting antennas, high-voltage (10KV) power transmission line, and grounding electrode networks. Its advantages are developing new frequency resource, high anti-interference power, stable and reliable signals, no blind region in transmission, low cost and high security and compatibility.
Description
The invention belongs to communication technical field, be specifically related to a kind of VLF ground wave telephone equipment.
Main telephone equipment and the radio telephone equipment of adopting of China rural area communication at present.Telephone equipment need set up special bar special line, and telephone signal is delivered to the user.The networking of this telephone mode expends a large amount of human and material resources, financial resources, builds the telephone network in a small towns, expensive hundreds thousand of units, and be subject to elemental destruction and artificial damage after the networking, and outline fault is many, and the maintenance and repair task is heavy.Radio telephone equipment though not vertical rod stringing must be built tall and big transmitting antenna tower, by the output of ionosphere wave straight-line transmitting, is easily blocked by the mountain deep valley, and the blind area is many, and coverage rate is low in the mountain area, and on-air radio electricity radio-frequency channel is crowded, mutually serious interference.
The present invention is directed to the prior art above shortcomings, purpose is to be the vast rural area of small towns village community (particularly mountainous rural area), a kind of 20-300KHz of selecting for use very low frequency frequency range is provided, propagates the VLF ground wave telephone equipment of telephone signal in the mode of face of land ground roll.
Technical scheme of the present invention is as follows:
The basic design of this equipment is, we individual consumer earthwave phone is sent into the earthwave phone power with the very low frequency carrier wave of the modulated tone signal of 20-300KHz through adapter and is amplified transmitter, transmitter amplifies synthetic output and the coupling of access ground connection sends network, after transmission antenna in the network and grounding electrode network I, II radiation, the very low frequency carrier wave is along ground surface, form with surface wave is transferred to the other side, and the other side passes to we with words in the same way, thereby realizes both sides' conversation.
VLF ground wave telephone equipment comprises that individual consumer's telephone set, switching machine, earthwave phone power are amplified transmitter, the ground connection coupling sends network and power supply.
Individual consumer's earthwave telephone set is by radiating circuit, and receiving circuit and dial-up circuit are formed.Radiating circuit is made up of voice amplifier, radio-frequency modulator, radio frequency amplifier, and its annexation is that speech amplification output connects radio-frequency modulator, and radio-frequency modulator output connects radio frequency amplifier.Receiving phone is made up of receiving preamplifier A, B, intermediate level frequency discrimination device, receipts voice amplifier and loud speaker, its annexation is that receiving preamplifier A, B output connects the intermediate level frequency discrimination device, the output of intermediate level frequency discrimination device receives voice amplifier, and amplifier output connects loud speaker.Dial-up circuit is by impulse sender, and the decoding decision device that collects the digits is formed, and its annexation is that impulse sender output receives number decoding decision device.In the VLF ground wave telephone equipment individual consumer earthwave telephone set, the voice amplifier of radiating circuit is by capacitor C 31-C36, resistance R 15-R21, and diode V13-V14, transmitter S2, integrated circuit D1E4069 forms.Radio-frequency modulator is by capacitor C 37, C41, resistance R 22, R28, and potentiometer W1, W2, diode V16-V19, triode V15, integrated circuit N2, D2 forms.Radiofrequency launcher is by capacitor C 1-C6, C12-C18, resistance R 10, and diode V9, V10, triode V1, V2, V7, V8, inductance T1, T2, T7, T8 form.Receiving preamplifier in the receiving circuit is by capacitor C 7-C12, V18-C24, resistance R 5-R6, R11-R12, and diode V5, V11, triode V6, V12, integrated circuit D1A-D1D, inductance T4-R6, T9-R12 form.The intermediate level frequency discrimination device is by capacitor C 42-C60, resistance R 29-R46, and diode V19, triode V19, integrated phone N3, inductance T14, T15, intermediate-frequency filter J1 forms.Receive voice amplifier by integrated circuit N4A (LM386), loud speaker S1, resistance R 40-46, capacitor C 54-C65 forms.Impulse sender is by capacitor C 62-C66, resistance R 47-R54, and triode V24, integrated circuit N5-WE1210, crystal X2, dial JP forms.Collect the digits the decoding decision device by capacitor C 67-C82, resistance R 50-R79, diode V26-V34, V36-V38, V40-V46, triode V25, V35, V39, crystal X3, integrated circuit N6MT8870, D3MC4028, D5A-D5C, on-hook button K1 forms.
The switching machine is by capacitor C 1-C6, resistance R 1-R18, and diode V1-V9, triode V10-V11, integrated circuit V1, D1-D4, N1, relay J 1, J2 forms.
The earthwave phone power is amplified transmitter by capacitor C 1-C17, resistance R 1-R21, and potentiometer W1-W7, triode V1-V6, integrated circuit N1, N2, power combiner is formed.
The ground connection coupling sends network by feeder line, impedance transformer, transmission antenna A, B10KV high-tension electricity transmission line, and grounding electrode network I, II form.Its annexation is that feed line output connects impedance transformer, and impedance transformer output two ends are sending and receiving letter antenna A, B respectively, and transmission antenna A, B end meet grounding electrode network I, II respectively.
VLF ground wave telephone equipment of the present invention is characterized in earthwave phone power amplification transmitter, the very low frequency carrier signal is sent into grounding electrode network I, the II of underground several Mi Shen by transmission antenna, after electromagnetic wave is opened from meter depths radiation of ground number, earth penetrating arrives ground vertically upward, the refraction back changes direction, and the form along the face of land with surface wave is propagated forward.Energy constantly penetrates the face of land and arrives near power line network in the propagation, and transmission antenna is sensed the carrier wave in the power line network simultaneously, in the stratum of " bleeding " again, and so forth, and " leakage " each other, energy complement improves transmittability greatly, to realize telecommunication.
The present invention and existing telephone communication equipment relatively have following outstanding advantage.
1. utilize and developed the new frequency resource of wireless communication field; Increasing at current radio wave frequency allocation pressure, all kinds of broadcast communication navigation have been crowded with under the situation of whole radio spectrum, and the surface wave telephone plant has developed the frequency resource of 20 to 300KHz very low frequency sections, has hewed out radio communication a slice new world.
2. strong interference immunity: VLF ground wave telephone equipment is owing to adopted low-frequency range electromagnetic wave and unique face of land ground roll transmission means of the idle not usefulness on China land, avoided interactive interference effectively with the on-air radio electric wave, each Subscriber Unit group network system adopts some formula frequently, does not also disturb each other.
3. signal stabilization is reliable: therefore the very low frequency surface wave, is not subjected to layer height variation sooner or later round the clock to influence signal and propagates (medium wave, shortwave broadcasting communication then are subject to this influence) not by aerial ionospheric reflection transmission, and signal stabilization is reliable.
4. transmission non-blind area: very low frequency surface wave phone transmission signal, just rise and fall with physical features along the face of land and advance, be not subjected to the mountain deep valley, the high building edifice block restriction, and the transmission non-blind area in mountain area communication networking, shows superior especially.
5. cost saving: VLF ground wave telephone equipment networking, neither need set up tall and big antenna launching tower, need not take up an area of yet and dig a pit, hole, etc., the vertical rod stringing, more do not have the outside line maintenance and repair, install and use simple and easy to doly, save a large amount of human and material resources, financial resources, with telephone networking ratio, economize on the use of funds about 90%.
6. strong security: the surface wave telephone plant adopts advanced digital coding, press the code dialing sender, the reception of decoding, and more difficult by free call on sb. else's expense through illegal means and eavesdropping than telephone, confidentiality is better.
7. compatible good: the surface wave telephone plant both can be in certain scope, independent networking, also can with the existing mutual networking of wired and Wireless Telecom Equipment, realize any telecommunication.
The invention will be further described below in conjunction with drawings and Examples:
Fig. 1 is a structured flowchart of the present invention;
Fig. 2 is individual consumer's telephone set network figure of the present invention;
Fig. 3 is that earthwave phone power of the present invention is amplified transmitter circuit figure;
Fig. 4 is earthwave call forwarding machine circuit figure of the present invention;
Fig. 5 is that ground connection of the present invention sends network.
Embodiment:
Referring to Fig. 1, VLF ground wave telephone equipment, propose the machine dialing by (we) individual consumer telephone set A, via the switching machine signal is sent into the earthwave phone power and amplify transmitter, the high-power signal of power amplification transmitter output, insert ground connection coupling transmission network radiation propagation through feeder line and open, signal is sent to (the other side) switching machine in the surface wave mode, change the other side individual consumer phone B over to; The signal that we are transmitted is reduced to speech through the receiving circuit demodulation, the individual phone B of the other side off-hook, and in the same manner described above voice signal is passed back to we, the both sides individual consumer realizes the telephone booth duplexing intercommunication conversation.
Individual consumer's telephone set network is seen shown in Figure 2: voice amplifier output connects radio-frequency modulator, and radio-frequency modulator output meets radio frequency amplifier A, B, and radio frequency amplifier A, B output inserts the switching machine.Receive preposition A, B output and connect the intermediate level frequency discrimination device, the output of intermediate level frequency discrimination device receives voice amplifier, and receive voice amplifier output and connect loud speaker, impulse sender output reception decision device, the decision device that collects the digits output receives voice amplifier.Voice amplifier is by capacitor C 31-C36, resistance R 15-R21, diode V13-V14, transmitter S2, integrated circuit DIE4069 forms, and its working method is, the voice signal that transmitter S2 produces is coupled to integrated circuit DIE4069 through C26 and amplifies output, send radio-frequency modulator.Radio-frequency modulator is by capacitor C 37, C41, resistance R 22, R28, potentiometer W1, W2, diode V16-V19, triode V15, integrated circuit N2, D2 forms, and its working method is, voice amplifier output C28 sends into integrated circuit N2, carrier wave is modulated, and modulated carrier amplifies through triode V15, sends into radio frequency amplifier by resistance R 22 couplings.Radiofrequency launcher is by capacitor C 1-C6, C13-C18, resistance R 10; Diode V9, V10, triode V1, V2, V7, V8, T1, T2, T7, T8 form under the inductance.Its working method is, the carrier wave that resistance R 22 is sent here is amplified by triode V1, V2, V9, V10 frequency-selecting, and the carrier signal of amplification is coupled to power amplifier through C89.Receiving preamplifier is by capacitor C 7-C12, C18-24, resistance R 15-R6, R11-R12, and diode V5, V11, triode V6, V12, integrated circuit DIA-DID, inductance T4-T6, T6-T12 form.Its working method is that the carrier signal that the other side sends is coupled to integrated circuit DIA-DID through C7, C18 and carries out the frequency-selecting amplification, exports access triode V6, V12 and amplifies once more, sends into the intermediate level frequency discrimination device by C24.The intermediate level frequency discrimination device is by capacitor C 42-C60, resistance R 29-R46, and diode V10, triode V19, integrated circuit N3, inductance T14, T15, intermediate-frequency filter J1 forms.Its working method is, the carrier signal that C33 sends here is carried out mixing, amplification, frequency discrimination, restore voice signal by R39 be coupled to receive voice amplifier, in the decoding decision device that collects the digits.Receive voice amplifier by integrated circuit N4A (LM386), loud speaker S1, resistance R 40-46, capacitor C 54-C65 forms, and its working method is that the voice signal that R39 is sent here is amplified by integrated circuit N4A, sends into loud speaker S1 by C55, is reduced into sound.Impulse sender is by capacitor C 62-C66, resistance R 47-R54, and triode V24, integrated circuit N5, WE1210, crystal X2, dial JP forms.Its working method is to be modulated in the middle of C57 is coupled to N1 (LM567) by the dialing signal that integrated circuit N5-WE1210 produces.Collect the digits decision device by capacitor C 64-C82, resistance 50-R79, diode V26-V34, V36-V38, V40-V46, triode V25, V35, V39, crystal X3, integrated circuit N6MT8870, D3MC4028, D5A-D5C, on-hook button K1 forms.Its working method is that the double-audio signal that R39 sends here is deciphered the operating state of being adjudicated and controlled complete machine by D5A-D5C by integrated circuit N6MT8870, D3MC4028.Bell position circuit is by C61, C85, C86, C88, resistance R 81-R89, and triode V21, V23, V48, V50, integrated circuit D5D, D6C-D6F, D1F, off-hook K switch 3 is formed.
The earthwave phone power is amplified the circuit of transmitter referring to shown in Figure 3, by capacitor C 1-C17, and resistance R 1-R21, potentiometer W1-W7, triode V1-V6, integrated circuit N1, N2, power combiner is formed.Its working method is, it is synthetic to carry out power after the carrier signal that the call forwarding machine is sent here is amplified by triode V1-V6 integrated circuit N1, N2, and the output of synthetic back is sent into the ground connection coupling and sent in the network.
The circuit of switching machine is referring to shown in Figure 4, by capacitor C1-C6, and resistance R 1-R18, diode V1-V9, triode V1-V10, integrated circuit V1, D1-D4, N1, relay J 1, J2 forms.Its working method is that the telephone set field intensity that individual consumer's phone is sent here detects with the decoding decision device, by integrated circuit V1, D1-D4, N1 control relay J1, J2, thereby has controlled the operating state of power amplifier and the break-make of speech, realizes switching.
The ground connection coupling sends network referring to shown in Figure 5, the signal of earthwave phone power synthesizer output, through feeder line, connect impedance transformer, the two ends of impedance transformer output are sending and receiving letter antenna A, B respectively, post a letter a day A, B along 10KV high-tension electricity transmission line is parallel set up certain distance after, end inserts grounding electrode network I, II respectively.
The course of work of the utility model VLF ground wave telephone equipment is: A master exhales: behind individual consumer's phone off-hook, by the blind sound of decoding decision device generation off-hook that collects the digits, through impulse sender with dial the number and send radio-frequency modulator, 20-300KHz carrier wave after the modulation send radiofrequency launcher, radiofrequency launcher output is sent into the earthwave phone power through adapter and is amplified transmitter, the high-power carrier signal of transmitter output is sent into the ground connection coupling by feeder line and is sent transmission antenna and grounding electrode network in the network, the very low frequency electromagnetic wave is after transmission antenna and the radiation of grounding electrode network, along the face of land, propagate arrival the other side forward with the form of surface wave.The other side's off-hook, we's sound of giving orders or instructions amplifies through voice amplifier and send radio frequency to send after sending frequency modulator to penetrate device, sending the earthwave phone power to amplify transmitter by adapter again amplifies, transmit the other side by the radiation of grounding electrode network, the other side converses after our receiving circuit receives the other side's carrier signal, send reception intermediate level frequency discrimination device through receiving preamplifier, send audio frequency amplifier, send loud speaker after the amplification through intermediate level frequency discrimination demodulation output audio signal; B is exhaled: after we's receiving preamplifier amplifies carrier signal during to party call, send intermediate frequency to put frequency discriminator, demodulate through intermediate level frequency discrimination and to send the decoding decision device that collects the digits the party call sign indicating number, after the demodulation judgment call sign indicating number unanimity, the ringing-current circuit send audio frequency amplifier to amplify ringing signal and send the loud speaker ring, we's off-hook, the ringing-current circuit will flow signal at stop, the other side gives orders or instructions, we receive preposition A, B will send into the intermediate level frequency discrimination device to square signal, send the receipts voice amplifier through the audio frequency letter of intermediate level frequency discrimination demodulation, and the audio signal after the amplification promotes loud speaker, finish the process of being exhaled, thereby realize both sides' conversational communication.
Claims (4)
1. VLF ground wave telephone equipment is selected 20-300KHz very low frequency frequency range for use, amplifies transmitter, ground connection coupling transmission network and power supply by individual consumer's telephone set, switching machine, earthwave phone power and forms, and it is characterized in that:
Individual consumer's telephone set comprises radiating circuit, receiving circuit, dial-up circuit, and its annexation is dial-up circuit output sending and receiving radio road, and radiating circuit output connects the power amplification transmitter;
The switching machine is by capacitor C 1-C6, resistance R 1-R18, and diode V1-V9, triode V10-V11, integrated circuit V1, D1-D4, N1, relay J 1, J2 forms;
The earthwave phone power is amplified transmitter by capacitor C 1-C17, resistance R 1-R21, and potentiometer W1-W7, triode V1-V6, integrated circuit N1, N2, power combiner is formed;
The ground connection coupling sends network by feeder line, impedance transformer, transmission antenna A, B, 10KV high-tension electricity transmission line, grounding electrode network I, II form, its annexation is that feed line output connects impedance transformer, and impedance transformer output two ends are sending and receiving letter antenna A, B respectively, and transmission antenna A, B end meet grounding electrode network I, II respectively.
2. very low frequency earthwave telephone plant according to claim 1, the radiating circuit that it is characterized in that individual consumer's telephone set is by voice amplifier, radio-frequency modulator, radio frequency amplifier A, B form, its annexation is that voice amplifier output connects radio-frequency modulator, and radio-frequency modulator output meets radio frequency amplifier A, B; Receiving circuit is by receiving preamplifier A, B, the intermediate level frequency discrimination device is received voice amplifier and loud speaker and is formed, and its annexation is that receiving preamplifier A, B output connects the intermediate level frequency discrimination device, intermediate level frequency discrimination output receives voice amplifier, receives voice amplifier output and connects loud speaker; Dial-up circuit is by impulse sender, and the decoding decision device that collects the digits is formed, and its annexation is that impulse sender output receives number decoding decision device.
3. VLF ground wave telephone equipment according to claim 2 is characterized in that voice amplifier, by capacitor C 31-C36, resistance R 15-R21, diode V13-V14, transmitter S2, integrated phone DIE4069 forms, radio-frequency modulator is by capacitor C 37, C41, resistance R 22, R28, potentiometer W1, W2, diode V16-V19, triode V15, integrated circuit N2, D2 form; Radiofrequency launcher is by capacitor C 1-C6, C13-C18, resistance R 10, and diode V9, V10, triode V1, V2, V7, V8, inductance T1, T2, T7, T8 form; Receiving preamplifier is by capacitor C 7-C17, C18-C24, resistance R 5-R6, R11-R12, and diode V5, V11, triode V6, V12, integrated circuit DIA-DID, inductance T4-R6, T9-R12 form; The intermediate level frequency discrimination device is by capacitor C 42-C53, resistance R 29-R39, and diode V19, triode V19, integrated circuit N3, inductance T14, T15, intermediate-frequency filter J1 forms; Receive voice amplifier by integrated circuit N4A (LM386), loud speaker S1, resistance R 40-46, capacitor C 54-C65 forms; Impulse sender is by capacitor C 62-C66, resistance R 47-R54, and triode V24, integrated circuit N5-WE1210, crystal X2, dial JP forms; Collect the digits the decoding decision device by capacitor C 67-C82, resistance R 50-R79, diode V26-V34, V36-V38, V40-V46, triode V25, V35, V39, crystal X3, integrated circuit N6MT8870, D3MC4028, D5A-D5C, on-hook button K1 forms.
4. according to claim 1 or 2 or 3 described VLF ground wave telephone equipments, it is characterized in that impedance transformer is that skeleton forms with the insulated conductor coiling by magnetic material or hollow material, transmission antenna A, transmission antenna B are plain conductor and along the parallel certain-length that sets up of high-tension electricity transmission line, and grounding electrode network I, II are netted horizontally embedded in underground at least 1 meter depths with plain conductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB981218091A CN1139194C (en) | 1998-10-21 | 1998-10-21 | VLF ground wave telephone equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB981218091A CN1139194C (en) | 1998-10-21 | 1998-10-21 | VLF ground wave telephone equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1251961A true CN1251961A (en) | 2000-05-03 |
| CN1139194C CN1139194C (en) | 2004-02-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB981218091A Expired - Fee Related CN1139194C (en) | 1998-10-21 | 1998-10-21 | VLF ground wave telephone equipment |
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| Country | Link |
|---|---|
| CN (1) | CN1139194C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102594462A (en) * | 2010-09-29 | 2012-07-18 | E-光谱技术公司 | Portable wireless through-the-earth communication system |
| CN105164852A (en) * | 2013-03-07 | 2015-12-16 | Cpg技术有限责任公司 | Excitation and use of guided surface wave modes on lossy media |
| CN108599810A (en) * | 2018-04-03 | 2018-09-28 | 电子科技大学 | A kind of system for across ground transmission signal |
| CN111615016A (en) * | 2020-04-26 | 2020-09-01 | 深圳震有科技股份有限公司 | Client terminal equipment driving method, device and storage medium |
-
1998
- 1998-10-21 CN CNB981218091A patent/CN1139194C/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102594462A (en) * | 2010-09-29 | 2012-07-18 | E-光谱技术公司 | Portable wireless through-the-earth communication system |
| CN102594462B (en) * | 2010-09-29 | 2015-04-29 | E-光谱技术公司 | Portable wireless through-the-earth communication system |
| CN105164852A (en) * | 2013-03-07 | 2015-12-16 | Cpg技术有限责任公司 | Excitation and use of guided surface wave modes on lossy media |
| CN105164852B (en) * | 2013-03-07 | 2018-05-11 | Cpg技术有限责任公司 | The excitation and use of guiding surface wave mode on lossy media |
| CN108599810A (en) * | 2018-04-03 | 2018-09-28 | 电子科技大学 | A kind of system for across ground transmission signal |
| CN111615016A (en) * | 2020-04-26 | 2020-09-01 | 深圳震有科技股份有限公司 | Client terminal equipment driving method, device and storage medium |
| CN111615016B (en) * | 2020-04-26 | 2022-04-29 | 深圳震有科技股份有限公司 | Client terminal equipment driving method, device and storage medium |
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| Publication number | Publication date |
|---|---|
| CN1139194C (en) | 2004-02-18 |
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