A single-ended powered fiber optic telephone system

Abstract

The present invention discloses a single-end powered fiber optic telephone system, comprising a powered telephone end, a non-powered telephone end and a single-mode optical fiber connecting the powered telephone end and the non-powered telephone end. The powered telephone end comprises a power supply unit, a power supply light source unit, a voice sending unit, a first voice receiving unit and a first wavelength division multiplexer, and the power supply unit provides power supply for the power supply light source unit, the voice sending unit and the first voice receiving unit; the non-powered telephone end comprises a light energy conversion power supply unit, a passive voice sending unit, a second voice receiving unit and a second wavelength division multiplexer, and the light energy conversion power supply unit provides power supply for the second voice receiving unit. One end of the single-mode optical fiber is optically connected to the voice sending unit, the first voice receiving unit and the powered light source unit through the first wavelength division multiplexer, and the other end is optically connected to the light energy conversion power supply unit, the second voice receiving unit and the passive voice sending unit through the second wavelength division multiplexer.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber communication, and in particular to a single-end powered optical fiber telephone system. Background Art

[0002] Fiber-optic communication is a technology that uses light to transmit information through an optical fiber. It boasts advantages such as long transmission distance, resistance to electromagnetic interference, wide bandwidth, and high reliability, making it widely used in fields such as the internet, television transmission, and military communications. However, in harsh environments such as underground mines and pipeline corridors, communication facilities are affected, limiting the application of traditional communication methods such as radio waves and microwave communications. The advantages of fiber-optic communication methods are becoming increasingly apparent. The emergence of fiber-optic telephones has solved the problem of point-to-point communication. Compared to traditional telephone communications, it not only enables more simultaneous voice data transmission and ensures stable and reliable communication, but also enables barrier-free communication in harsh environments, making it the preferred method for long-distance voice communication.

[0003] Fiber-optic telephones operate by converting electrical signals at the transmitting end into optical signals through two photoelectric conversion steps, and then converting them back into electrical signals at the receiving end. With the continuous advancement of communications technology, wavelength division multiplexing (WDM) technology has been used to combine multiple wavelengths of optical signals for transmission within a single optical fiber. This not only increases transmission capacity and network transmission efficiency, but also reduces operating costs. It enables a variety of services, including telephone and video calls, making it ideal for point-to-point fiber-optic voice and video communications.

[0004] However, the vast majority of fiber optic devices are passive, which has limited the development of fiber optic sensing technology. Introducing active optical devices in underground mines and pipeline corridors often requires a continuous external power supply, which increases system costs. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a single-ended powered fiber optic telephone system that realizes two-way voice transmission by powering one end. The single-ended powered fiber optic telephone system comprises:

[0006] A power supply telephone end, comprising a power supply unit, a power supply light source unit, a voice sending unit, a first voice receiving unit and a first wavelength division multiplexer, wherein the power supply unit provides power supply to the power supply light source unit, the voice sending unit and the first voice receiving unit;

[0007] The non-powered telephone terminal includes a light energy conversion power supply unit, a passive voice sending unit, a second voice receiving unit and a second wavelength division multiplexer, wherein the light energy conversion power supply unit provides power supply for the second voice receiving unit;

[0008] A single-mode optical fiber is connected to the powered telephone end and the non-powered telephone end, one end of which is connected to the voice sending unit, the first voice receiving unit, and the power supply light source unit through the first wavelength division multiplexer, and the other end of which is connected to the light energy conversion power supply unit, the second voice receiving unit, and the passive voice sending unit through the second wavelength division multiplexer.

[0009] The voice sending unit provides signal light with a first wavelength λ1 as the center wavelength to the second voice receiving unit, the passive voice sending unit provides signal light with a second wavelength λ2 as the center wavelength to the first voice receiving unit, and the power supply light source unit provides energy light with a third wavelength λ3 as the center wavelength to the light energy conversion power supply unit.

[0010] Furthermore, the voice sending unit includes a microphone, a signal converter and an optical transmitting end electrically connected in sequence, and the optical transmitting end is connected to the first wavelength division multiplexer optical fiber; the second voice receiving unit includes an optical receiving end and a power amplifier electrically connected in sequence, and a second earpiece and a second speaker electrically connected to the power amplifier, and the optical receiving end is connected to the second wavelength division multiplexer optical fiber.

[0011] Furthermore, the passive voice sending unit includes a reflection unit and an optical fiber coil connected in sequence by optical fiber, and the optical fiber coil is optically connected to the second wavelength division multiplexer; the first voice receiving unit includes a first photodetector and a demodulation module electrically connected in sequence, a first earpiece and a first speaker electrically connected to the demodulation module, and an interference module optically connected to the first photodetector, and the interference module is optically connected to the first wavelength division multiplexer.

[0012] Furthermore, the light energy conversion power supply unit includes a second photodetector and a DC power supply unit electrically connected in sequence, the second photodetector is optically connected to the second wavelength division multiplexer, and the DC power supply unit is electrically connected to the second voice receiving unit.

[0013] Furthermore, part of the energy light with a central wavelength of the third wavelength λ3 of the power supply light source unit at the powered telephone end is used to perform Raman amplification on the signal light with a central wavelength of the first wavelength λ1 and the signal light with a central wavelength of the second wavelength λ2; the other part is converted into electrical energy at the non-powered telephone end and provides power supply for the second voice receiving unit at the non-powered telephone end.

[0014] Furthermore, the energy light having a central wavelength of the third wavelength λ3 provided by the energy supply light source unit enhances the signal light having a central wavelength of the first wavelength λ1 and the signal light having a central wavelength of the second wavelength λ2 through a Raman amplification effect, and the Raman gain is expressed by the following formula:

[0015] ,

[0016] in is the Raman gain, is the Raman gain coefficient, is the optical power of the energy supply light source unit, is the effective fiber length.

[0017] Furthermore, the frequency difference between the energy light having the third wavelength λ3 as the center wavelength, the signal light having the first wavelength λ1 as the center wavelength, and the signal light having the second wavelength λ2 as the center wavelength is expressed by the following formula:

[0018] ,

[0019] .

[0020] Furthermore, the Raman amplification efficiency It is expressed by the following formula:

[0021] .

[0022] Furthermore, the energy light of the other part with the central wavelength of the third wavelength λ3 is received by the second photodetector of the non-powered telephone end and converted into electrical energy, and the photoelectric conversion efficiency of the energy light with the central wavelength of the third wavelength λ3 is It is expressed by the following formula:

[0023] ,

[0024] Wherein, CE is the photoelectric conversion coefficient of the second photodetector, and

[0025] ,

[0026] Where QE is quantum efficiency; is the absorption coefficient; is the material thickness.

[0027] Furthermore, the comprehensive utilization rate of Raman amplification efficiency and photoelectric conversion efficiency It is expressed by the following formula:

[0028] .

[0029] The single-ended powered fiber optic telephone system provided by the present invention connects the fiber optic telephones at both ends through the single-mode optical fiber, and only provides power supply to the powered telephone end, and remotely powers the non-powered telephone end through the energy light of the powered telephone end. The non-powered telephone end does not require an additional power supply, which greatly saves costs and reduces energy consumption.

[0030] Moreover, the present invention utilizes wavelength division multiplexing technology and uses only one core optical fiber to transmit signal light and energy light of different wavelengths in the same core, and based on the use of optical signals of the same wavelength between transmission and reception, ensures the stable transmission of sound signals over long distances. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a schematic diagram of a single-ended powered fiber optic telephone system of the present invention.

[0033] Figure 2 Schematic diagram of the application of the single-ended powered fiber optic telephone system of the present invention in underground mines. DETAILED DESCRIPTION

[0034] Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are merely some, and not all, of the embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the description of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0035] The directions or positional relationships indicated by terms such as "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience and simplification of description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0036] The terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of elements other than the listed elements and may also include additional elements not specifically listed.

[0037] See also Figure 1 The present invention provides a single-ended powered fiber optic telephone system, comprising:

[0038] The power supply telephone terminal 100 includes a power supply unit 110, a power supply light source unit 120, a voice sending unit 130, a first voice receiving unit 140 and a first wavelength division multiplexer 150. The power supply unit 110 provides power supply to the power supply light source unit 120, the voice sending unit 130 and the first voice receiving unit 140;

[0039] The non-powered telephone terminal 200 includes a light energy conversion power supply unit 220, a passive voice sending unit 240, a second voice receiving unit 230 and a second wavelength division multiplexer 210. The light energy conversion power supply unit 220 provides power supply for the second voice receiving unit 230.

[0040] The single-mode optical fiber 300 connects the powered telephone terminal 100 and the non-powered telephone terminal 200. One end of the single-mode optical fiber 300 is connected to the voice sending unit 130, the first voice receiving unit 140, and the power supply light source unit 120 through the first wavelength division multiplexer 150, and the other end of the single-mode optical fiber 300 is connected to the light energy conversion power supply unit 220, the second voice receiving unit 230, and the passive voice sending unit 240 through the second wavelength division multiplexer 210.

[0041] In which, the voice sending unit 130 provides signal light of the first wavelength λ1 to the second voice receiving unit 230, the passive voice sending unit 240 provides signal light of the second wavelength λ2 to the first voice receiving unit 140, and the power supply light source unit 120 provides energy light of the third wavelength λ3 to the light energy conversion power supply unit 220.

[0042] The voice sending unit 130 includes a microphone 131, a signal converter 132 and an optical transmitting end 133 electrically connected in sequence, and the optical transmitting end 133 is optically connected to the first wavelength division multiplexer 150; the second voice receiving unit 230 includes an optical receiving end 231 and a power amplifier 232 electrically connected in sequence, and a second earpiece 233 and a second speaker 234 electrically connected to the power amplifier 232, and the optical receiving end 231 is optically connected to the second wavelength division multiplexer 210.

[0043] The passive voice sending unit 240 includes a reflection unit 241 and an optical fiber coil 242 connected in sequence by optical fiber, and the optical fiber coil 242 is optically connected to the second wavelength division multiplexer 210; the first voice receiving unit 140 includes a first photodetector 142 and a demodulation module 143 electrically connected in sequence, a first earpiece 144 and a first speaker 145 electrically connected to the demodulation module 143, and an interference module 141 connected to the first photodetector 142 by optical fiber, and the interference module 141 is optically connected to the first wavelength division multiplexer 150.

[0044] The light energy conversion power supply unit 220 includes a second photodetector 221 and a DC power supply unit 222 electrically connected in sequence. The second photodetector 221 is optically connected to the second wavelength division multiplexer 210 , and the DC power supply unit 222 is electrically connected to the second voice receiving unit 230 .

[0045] Part of the energy light of the third wavelength λ3 of the power supply light source unit 120 of the powered telephone end 100 is used to perform Raman amplification on the signal light of the first wavelength λ1 and the signal light of the second wavelength λ2; the other part is converted into electrical energy at the non-powered telephone end 200 and provides power supply for the second voice receiving unit 230 of the non-powered telephone end 200.

[0046] In this embodiment, the signal light having the first wavelength λ1 as the center wavelength and the signal light having the second wavelength λ2 as the center wavelength are both signal lights having center wavelengths within the C band.

[0047] More specifically, the output end of the power supply unit 110 is connected to the power supply light source unit 120, and the power supply light source unit 120 outputs high-power energy light with a central wavelength of the third wavelength λ3. In this embodiment, the energy light with a central wavelength of the third wavelength λ3 is selected as energy light with a central wavelength of 1455 nm, and is connected to the first wavelength division multiplexer 150 through the single-mode optical fiber 300.

[0048] The first wavelength division multiplexer 150 is connected to the second wavelength division multiplexer 210 through the single-mode optical fiber 300. The high-power 1455 nm energy light with a central wavelength of the third wavelength λ3 can be Raman amplified with a first wavelength λ1 and a second wavelength λ2 as the central wavelengths within the C-band transmitted by the optical transmitting end 133 and the optical fiber coil 242 during transmission through the single-mode optical fiber 300.

[0049] The input end of the first wavelength division multiplexer 150 and the output end of the second wavelength division multiplexer 210 are divided into three paths. The energy light output by the power supply light source unit 120 is connected to the second photodetector 221 through the single-mode optical fiber 300, and then connected to the DC power supply unit 222. The DC power supply unit 222 provides power supply for the optoelectronic devices of the second voice receiving unit 230.

[0050] The output end of the microphone 131 of the voice sending unit 130 of the power supply telephone end 100 is connected to the signal converter 132, the output end of the signal converter 132 is connected to the optical sending end 133, and the output end of the optical sending end 133 and the input end of the interference module 141 are connected to the first wavelength division multiplexer 150 together.

[0051] The optical transmitting end 133 outputs signal light with a specific central wavelength of the first wavelength λ1 within the C band, and then enters the second wavelength division multiplexer 210. Thereafter, the optical receiving end 231 is connected to the output end of the second wavelength division multiplexer 210 through the single-mode optical fiber 300. The optical receiving end 231 receives the signal light with the central wavelength of the first wavelength λ1, and is connected to the second handset 233 and the second speaker 234 by accessing the power amplifier 232, thereby realizing voice transmission from the powered telephone end 100 to the non-powered telephone end 200.

[0052] After being subjected to sound vibration, the optical fiber coil 242 of the non-powered telephone end 200 changes the phase of the signal light having a second wavelength λ2 as a specific central wavelength within the C band. The optical signal with the changed wavelength is transmitted to the second wavelength division multiplexer 210 via the reflection unit 241. Subsequently, the output end of the second wavelength division multiplexer 210 is connected to the first wavelength division multiplexer 150 via the single-mode optical fiber 300. The first wavelength division multiplexer 150 is connected to the interference module 141 via an optical fiber. The output end of the interference module 141 is connected to the first photodetector 142. The first photodetector 142 is connected to the demodulation module 143 and completes the restoration of the voice signal of the passive voice transmission unit 240 of the non-powered telephone end 200. The demodulation module 143 realizes voice transmission from the non-powered telephone end 200 to the powered telephone end 100 by connecting to the first receiver 144 and the first speaker 145.

[0053] In this embodiment, the first wavelength division multiplexer 150 and the power supply light source unit 120, the first wavelength division multiplexer 150 and the optical transmitting end 133, the first wavelength division multiplexer 150 and the interference module 141, the second wavelength division multiplexer 210 and the second photodetector 221, the second wavelength division multiplexer 210 and the optical receiving end 231, and the second wavelength division multiplexer 210 and the optical fiber coil 242 are also connected using the single-mode optical fiber 300; the second photodetector 221 and the DC power supply unit 222, the microphone 131 and the signal converter 132, the optical receiving end 231 and the power amplifier 232, the power amplifier 232 and the second earpiece 233 and the second speaker 234, the first photodetector 142 and the demodulation module 143, the demodulation module 143 and the first earpiece 144 and the first speaker 145 are connected through power lines.

[0054] In more detail, in this embodiment, the power supply light source unit 120 is used to: emit high-power energy light with a central wavelength of a third wavelength λ3 of 1455 nm, first Raman amplify the C-band optical signal between the powered telephone end 100 and the non-powered telephone end 200, and the remaining part supplies power to the non-powered telephone end 200.

[0055] The second photodetector 221 is used to: after the signal light with the central wavelength of the first wavelength λ1 and the central wavelength of the second wavelength λ2 is removed by the second wavelength division multiplexer 210, the photodiode of the second photodetector 221 receives the signal as an electrical signal and supplies it to the DC power supply unit 222, and the DC power supply unit 222 supplies power to the second voice receiving unit 230 of the non-powered telephone end 200.

[0056] The optical transmitting end 133 is used to modulate the electrical signal input from the microphone 131 via the signal converter 132 and convert it into a signal light with a center wavelength of the first wavelength λ1 in the C band, thereby further transmitting the voice information of the powered telephone end 100 to the non-powered telephone end 200.

[0057] The optical receiving end 231 is used to convert the received signal light of the first wavelength λ1 of the central wavelength in the C band into an electrical signal through phase demodulation, amplitude demodulation and other methods, and then extract the original signal from the electrical signal amplified by the power amplifier 232 for use in the second earpiece 233 and the second speaker 234.

[0058] The optical fiber coil 242 is configured to cause a slight strain on the optical fiber when sound waves propagate through the optical fiber coil 242 , thereby causing a change in the refractive index of the optical fiber itself, thereby changing the phase of the signal light having a second wavelength λ2 as the central wavelength transmitted within the C-band of the optical fiber. The signal light having the second wavelength λ2 as the central wavelength after the phase change passes through the reflection unit 241 and enters the second wavelength division multiplexer 210 , ultimately reaching the power supply telephone terminal 100 . After interference by the interference module 141 , photoelectric conversion by the first photodetector 142 , and demodulation by the demodulation module 143 , the original voice information is obtained, and the voice is ultimately received through the first receiver 144 and the first speaker 145 .

[0059] In summary, in the present invention, the microphone 131, the signal converter 132, the optical transmitting end 133, the first wavelength division multiplexer 150, the single-mode optical fiber 300, the second wavelength division multiplexer 210, the optical receiving end 231, the power amplifier 232, the second handset 233, and the second speaker 234 are a unidirectional voice transmission line from the powered telephone end 100 to the non-powered telephone end 200. The electrical signal is converted into an optical signal and then into an electrical signal through the optical transmitting end 133 and the optical receiving end 231. After passing through the first wavelength division multiplexer 150 and the second wavelength division multiplexer 210, the signal light with the central wavelength of the first wavelength λ1 in a specific C band transmitted between the two ends of the optical fiber telephone remains unchanged. The original information is obtained by demodulation to reduce signal distortion.

[0060] In the present invention, the optical fiber coil 242, the reflecting unit 241, the second wavelength division multiplexer 210, the single-mode optical fiber 300, the first wavelength division multiplexer 150, the interference module 141, the first photodetector 142, the demodulation module 143, the first receiver 144, and the first speaker 145 constitute a one-way voice transmission line from the non-powered telephone end 200 to the powered telephone end 100. The collected sound signals are directly converted into phase changes through the optical fiber coil 242. These signals are finally demodulated to obtain the original sound waveform, and voice transmission can be achieved at the non-powered telephone end 200 without powering.

[0061] See also Figure 2 The present invention is applied in areas with harsh environments such as underground mines and pipeline corridors or remote areas with poor signals. Through the single-ended power supply fiber optic telephone system, one-way power supply can be achieved between points, completing long-distance real-time and accurate calls.

[0062] In this example, based on the single-ended powered fiber optic telephone system, the optical conversion efficiency of a high-power light source having a central wavelength of 1455 nm and a third wavelength λ3 is calculated. The light source having a central wavelength of 1455 nm and a third wavelength λ3 has two uses. First, it performs Raman amplification on the C-band signal light having a central wavelength of the first wavelength λ1 and the signal light having a central wavelength of the second wavelength λ2. The remaining light is then converted into electrical energy by the second photodetector 221.

[0063] In this embodiment, the energy light of 1455 nm with a central wavelength of the third wavelength λ3 provided by the energy supply light source unit 120 can enhance the signal light with a central wavelength of the first wavelength λ1 and the signal light with a central wavelength of the second wavelength λ2 through the Raman amplification effect, wherein the Raman gain is expressed by the following formula:

[0064] ,

[0065] in is the Raman gain, is the Raman gain coefficient, is the optical power of the energy supply light source unit 120, is the effective fiber length.

[0066] Furthermore, the frequency difference between the energy light having the third wavelength λ3 as the center wavelength, the signal light having the first wavelength λ1 as the center wavelength, and the signal light having the second wavelength λ2 as the center wavelength is expressed by the following formula:

[0067] ,

[0068] .

[0069] Raman amplification efficiency It is expressed by the following formula:

[0070] .

[0071] Furthermore, part of the energy light with a central wavelength of the third wavelength λ3 of the power supply light source unit 120 of the power supply telephone end 100 is used to perform Raman amplification on the signal light with a central wavelength of the first wavelength λ1 and the signal light with a central wavelength of the second wavelength λ2; the other part is converted into electrical energy at the non-power supply telephone end 200 and provides power supply for the second voice receiving unit 230 of the non-power supply telephone end 200, while the other part of the energy light with a central wavelength of the third wavelength λ3 is received by the second photodetector 221 of the non-power supply telephone end 200 and converted into electrical energy, and the photoelectric conversion efficiency of the energy light with a central wavelength of the third wavelength λ3 is It is expressed by the following formula:

[0072] ,

[0073] The ability of the photodiode of the second photodetector 221 to convert incident photons into electron pairs can be represented by the conversion efficiency CE (Conversion Efficiency), that is, CE is the photoelectric conversion coefficient of the second photodetector 221, and

[0074] ,

[0075] Among them, QE is quantum efficiency, which is mainly related to the composition ratio and manufacturing process; is the absorption coefficient, which is related to the band structure of the material and the wavelength of the incident light; is the material thickness, that is, the thickness of the photodiode. In this embodiment, the photodiode is an indium gallium arsenide diode.

[0076] Therefore, the comprehensive utilization rate of Raman amplification efficiency and photoelectric conversion efficiency is obtained. It is expressed by the following formula:

[0077] .

[0078] The single-ended powered fiber optic telephone system provided by the present invention has the following beneficial effects:

[0079] 1. The present invention connects the fiber optic telephones at both ends through a single-mode optical fiber, only providing power supply to the powered telephone end, and remotely powers the non-powered telephone end through the energy light of the powered telephone end. The non-powered telephone end does not require additional power supply, which greatly saves costs and reduces energy consumption.

[0080] 2. The present invention uses high-power 1455 nm wavelength energy light to firstly be used for Raman amplification of the transmitted C-band light source, and the remaining light energy is converted into electrical energy at the receiving end to provide power supply for the second voice receiving part of the non-powered telephone end.

[0081] 3. The present invention uses two sets of voice transmission methods. One set is the conversion of electrical signals into optical signals and then into electrical signals. It uses the signal light with the center wavelength of the first wavelength λ1 in the C band for long-distance transmission, and changes the light intensity in the sound-transmitting single-mode optical fiber by changing the frequency of the electrical signal. Finally, the received light is demodulated into the original electrical signal through the power amplifier, and then the original sound information is obtained; the other set modulates the phase change of the signal light with the center wavelength of the second wavelength λ2 in the C band by sound vibration, demodulates it into an electrical signal, and finally restores the original sound information.

[0082] 4. The present invention utilizes wavelength division multiplexing technology and uses only one core optical fiber to transmit signal light and energy light of different wavelengths on the same core. Based on the use of optical signals of the same wavelength between transmission and reception, it ensures the stable transmission of sound signals over long distances.

[0083] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with this technical field within the technical scope disclosed in the present invention should be covered by the scope of protection of the present invention.

Claims

1. A single-ended powered fiber optic telephone system, characterized in that: include: A power supply telephone end, comprising a power supply unit, a power supply light source unit, a voice sending unit, a first voice receiving unit and a first wavelength division multiplexer, wherein the power supply unit provides power supply to the power supply light source unit, the voice sending unit and the first voice receiving unit; The non-powered telephone terminal includes a light energy conversion power supply unit, a passive voice sending unit, a second voice receiving unit and a second wavelength division multiplexer, wherein the light energy conversion power supply unit provides power supply for the second voice receiving unit; A single-mode optical fiber is connected to the powered telephone end and the non-powered telephone end, one end of which is connected to the voice sending unit, the first voice receiving unit, and the power supply light source unit through the first wavelength division multiplexer, and the other end of which is connected to the light energy conversion power supply unit, the second voice receiving unit, and the passive voice sending unit through the second wavelength division multiplexer. The voice sending unit provides signal light with a first wavelength λ1 as the center wavelength to the second voice receiving unit, the passive voice sending unit provides signal light with a second wavelength λ2 as the center wavelength to the first voice receiving unit, and the power supply light source unit provides energy light with a third wavelength λ3 as the center wavelength to the light energy conversion power supply unit.

2. The single-ended powered fiber optic telephone system according to claim 1, wherein: The voice sending unit includes a microphone, a signal converter and an optical transmitting end electrically connected in sequence, and the optical transmitting end is connected to the optical fiber of the first wavelength division multiplexer; the second voice receiving unit includes an optical receiving end and a power amplifier electrically connected in sequence, and a second earpiece and a second speaker electrically connected to the power amplifier, and the optical receiving end is connected to the optical fiber of the second wavelength division multiplexer.

3. The single-ended powered fiber optic telephone system according to claim 1, wherein: The passive voice sending unit includes a reflection unit and an optical fiber coil connected in sequence by optical fiber, and the optical fiber coil is optically connected to the second wavelength division multiplexer; the first voice receiving unit includes a first photodetector and a demodulation module electrically connected in sequence, a first earpiece and a first speaker electrically connected to the demodulation module, and an interference module optically connected to the first photodetector, and the interference module is optically connected to the first wavelength division multiplexer.

4. The single-ended powered fiber optic telephone system according to claim 1, wherein: The light energy conversion power supply unit includes a second photodetector and a DC power supply unit electrically connected in sequence, the second photodetector is optically connected to the second wavelength division multiplexer, and the DC power supply unit is electrically connected to the second voice receiving unit.

5. The single-ended powered fiber optic telephone system according to claim 1, wherein: Part of the energy light with a central wavelength of the third wavelength λ3 of the power supply light source unit at the powered telephone end is used to perform Raman amplification on the signal light with a central wavelength of the first wavelength λ1 and the signal light with a central wavelength of the second wavelength λ2; the other part is converted into electrical energy at the non-powered telephone end and provides power supply for the second voice receiving unit at the non-powered telephone end.

6. The single-ended powered fiber optic telephone system according to claim 5, wherein: The energy light having a central wavelength of the third wavelength λ3 provided by the energy supply light source unit enhances the signal light having a central wavelength of the first wavelength λ1 and the signal light having a central wavelength of the second wavelength λ2 through the Raman amplification effect. The Raman gain is expressed by the following formula: Among them G v (Δv) is the Raman gain, g v (Δv) is the Raman gain coefficient, is the optical power of the energy source unit, L eff is the effective fiber length.

7. The single-ended powered fiber optic telephone system according to claim 6, wherein: The frequency difference between the energy light having the third wavelength λ3 as the center wavelength, the signal light having the first wavelength λ1 as the center wavelength, and the signal light having the second wavelength λ2 as the center wavelength is expressed by the following formula:

8. The single-ended powered fiber optic telephone system according to claim 6, wherein: Raman amplification efficiency δ R It is expressed by the following formula:

9. The single-ended powered fiber optic telephone system according to claim 6, wherein: The energy light of the other part with the central wavelength of the third wavelength λ3 is received by the second photodetector of the non-powered telephone end and converted into electrical energy. The photoelectric conversion efficiency δ of the energy light with the central wavelength of the third wavelength λ3 is E It is expressed by the following formula: Wherein, CE is the photoelectric conversion coefficient of the second photodetector, and CE=QE×(1-e -αd ), Where QE is the quantum efficiency; α is the absorption coefficient; and d is the material thickness.

10. The single-ended powered fiber optic telephone system according to claim 9, wherein: Comprehensive utilization rate of Raman amplification efficiency and photoelectric conversion efficiency δ Total It is expressed by the following formula:

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