An analog optical emission module integrating multi-channel wavelength division multiplexing

Abstract

The present invention relates to an analog optical emission module integrated with multi-channel wavelength division multiplexing. It mainly includes a radio frequency modulation component, a laser component, a laser control circuit, a wavelength division multiplexing component, and a packaging housing. Among them, the radio frequency modulation component is used to process and transmit analog microwave signals and load the analog microwave signals onto the laser component; the laser component is used to realize the electro-optical conversion of analog microwave signals into optical signals and beam shaping; the laser control circuit is used to provide constant current and constant temperature control for the laser component; the wavelength division multiplexing component is used to multiplex the combined waves of optical signals of multiple different wavelength channels into one path; the packaging housing is used to realize the integrated packaging of the radio frequency modulation component, the laser component, the laser control circuit, and the wavelength division multiplexing component. The present invention has the advantages of high integration, low power consumption, small volume, strong wavelength division multiplexing ability, large electromagnetic shielding efficiency, high reliability, etc., and is suitable for a wider range of application requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber communication, and particularly to an analog optical transmission module integrating multi-channel wavelength division multiplexing. Background Art

[0002] Radio-over-fiber (RoF) technology combines the advantages of optical fiber communication technology such as large bandwidth, low loss, strong multiplexing ability, and small volume, as well as the advantages of wireless communication technology such as low cost and flexible access. It uses optical fibers to transmit analog microwave signals and has very broad application prospects in system fields such as broadband access networks, intelligent transportation systems, radars, and airborne communications.

[0003] As the core component of a radio-over-fiber communication system, an analog optical transmission module realizes the conversion and modulation of microwave signals into optical signals. Most of the analog optical transmission modules on the current market are composed of discrete sub-modules such as radio frequency modulators, lasers, control circuit boards, and wavelength division multiplexers. In addition, since the optical path of the analog optical module needs to match a one-to-one radio frequency circuit and considering the factor of electromagnetic shielding, there are often problems such as too large channel spacing or unequal channel spacings, which are not conducive to multi-channel integration and even less convenient for integrating the wavelength division multiplexing function. Therefore, the existing analog optical transmission modules have problems such as large volume, limited multi-channel integration, high power consumption, inability to integrate wavelength division multiplexing, and poor environmental adaptability, which greatly limit their applications in fields such as wireless communication, phased array radars, and airborne communications.

[0004] In view of this, how to overcome the defects or meet the requirements of the existing technology and solve the above technical problems is a difficult problem to be solved in this technical field. Summary of the Invention

[0005] In view of the defects or improvement requirements in the existing technology: the existing analog optical transmission modules have problems such as large volume, limited multi-channel integration, and inability to integrate wavelength division multiplexing. The present invention proposes an analog optical transmission module integrating multi-channel wavelength division multiplexing, which integrates functions such as radio frequency modulation, electro-optical conversion, and wavelength division multiplexing, and has advantages such as high integration, low power consumption, small volume, high reliability, and strong wavelength division multiplexing ability, and is suitable for a wider range of application requirements.

[0006] The embodiments of the present invention adopt the following technical solutions:

[0007] The present invention provides an analog optical emission module integrating multi-channel wavelength division multiplexing, which includes a radio frequency modulation component, a laser component, a laser control circuit, a wavelength division multiplexing component, and a packaging housing. Among them, the radio frequency modulation component is used to process and transmit an analog microwave signal, and load the analog microwave signal onto the laser component; the laser component is used to realize the electro-optical conversion of the analog microwave signal into an optical signal and beam shaping; the laser control circuit is used to provide constant current and constant temperature control for the laser component; the wavelength division multiplexing component is used to multiplex the combined wave of optical signals of multiple different wavelength channels into one path; the packaging housing is used to realize the integrated packaging of the radio frequency modulation component, the laser component, the laser control circuit, and the wavelength division multiplexing component.

[0008] Further, the radio frequency modulation component includes a microwave transmission line, a fixed attenuator, and a low noise amplifier. The analog microwave signal is transmitted in the radio frequency modulation component through the microwave transmission line at the input end, and after passing through the fixed attenuator and the low noise amplifier in sequence, it is then loaded onto the laser component through the microwave transmission line at the output end.

[0009] Further, the radio frequency modulation component includes a microwave transmission line, a variable attenuator, a low noise amplifier, a splitter, and a detector. The analog microwave signal is transmitted in the radio frequency modulation component through the microwave transmission line at the input end, and after passing through the variable attenuator and the low noise amplifier in sequence, it is split into two signals by the splitter. Among them, a part of the analog microwave signal continues to be transmitted along the transmission arm of the splitter and is loaded onto the laser component through the microwave transmission line at the output end, and the remaining part of the analog microwave signal is coupled to the detector through the coupling arm of the splitter, so that the main control board adjusts the control voltage according to the microwave signal detected by the detector and changes the gain value of the variable attenuator.

[0010] Further, the laser component includes a cooler, a heat sink, a transition block, a laser chip, a backlight detector, a thermistor, a collimating lens, and an optical isolator. Among them, the laser chip, the backlight detector, and the thermistor are assembled on the transition block, the transition block, the collimating lens, and the optical isolator are assembled on the heat sink, the heat sink is assembled on the cooler, and the cooler, the thermistor, the backlight detector, and the laser control circuit are combined to realize the constant temperature control and constant current control of the laser component.

[0011] Furthermore, the wavelength division multiplexing component includes a steering prism, a filter, a glass substrate, an anti-reflection film, an anti-reflection film, and a shielding absorber. The incident end face and the exit end face of the glass substrate are designed with an inclined angle. There are multiple filters, which are sequentially assembled on the incident end face of the glass substrate at a fixed interval. The anti-reflection film and the anti-reflection film are assembled on the exit end face of the glass substrate. The shielding absorber is used to absorb the electromagnetic fields radiated by each channel radio frequency modulation component.

[0012] Furthermore, the wavelength division multiplexing component further includes a spacer block. The glass substrate, the steering prism, and the shielding absorber are fixed on the spacer block. The anti-reflection film is assembled on the acute angle side of the exit end face of the glass substrate, and the anti-reflection film is assembled on the obtuse angle side of the exit end face of the glass substrate.

[0013] Furthermore, there are multiple steering prisms, which are respectively used to horizontally turn the light beams passing through them, and convert multiple channel light beams with unequal intervals or large intervals into multi-channel light beams with smaller and equal intervals.

[0014] Furthermore, the steering prism includes a first steering prism, a second steering prism, and a third steering prism. After the first channel light beam passes through the first steering prism, it successively passes through the filter and the glass substrate, and then exits from the anti-reflection film. After the second channel light beam passes through the second steering prism, it enters through the filter, propagates three times in the glass substrate, and then exits through the anti-reflection film. After the third channel light beam passes through the third steering prism, it enters through the filter, propagates five times in the glass substrate, and then exits through the anti-reflection film. The fourth channel light beam directly enters the filter, then propagates seven times in the glass substrate, and then exits through the anti-reflection film. The four channel light beams are combined and output at the anti-reflection film.

[0015] Furthermore, the steering prism includes a fourth steering prism, a fifth steering prism, a sixth steering prism, and a seventh steering prism. Four non-equidistant light beams of the first channel, the second channel, the fourth channel, and the fifth channel respectively pass through the fourth steering prism, the fifth steering prism, the sixth steering prism, and the seventh steering prism, and then form five equidistant parallel light beams with a smaller channel interval together with the third channel reference light beam, so as to realize the conversion of multi-channel light beams with a large interval and unequal intervals into multi-channel light beams with a smaller and equal interval, and then realize the multiplexing function through the filter, the glass substrate, the anti-reflection film, and the anti-reflection film.

[0016] Furthermore, it further includes a radio frequency connector, a tail tube, and an output optical fiber. The packaging shell includes a box body, a box body cavity, a box body outer cavity, an upper cover plate of the box body cavity, and a lower cover plate of the box body outer cavity. Specifically:

[0017] The RF connector is sintered at one end of the box body, and the tail tube is sintered at the other end of the box body. The RF modulation component, the laser component, and the wavelength division multiplexing component are sequentially encapsulated on the base of the inner cavity of the box body. The laser control circuit is encapsulated in the groove of the outer cavity of the box body. The upper cover plate of the inner cavity of the box body is encapsulated on the upper surface of the inner cavity of the box body. The lower cover plate of the outer cavity of the box body is fixed on the lower surface of the outer cavity of the box body. After the multi-channel optical signals are multiplexed by wavelength division through the wavelength division multiplexing component, they are coupled to the output optical fiber, and the coupling end of the output optical fiber is fixed in the tail tube.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] (1) The analog light source module integrating multi-channel wavelength division multiplexing proposed by the present invention realizes the integrated packaging of the RF modulation component, the laser component, the wavelength division multiplexing component, and the control circuit, significantly improves the packaging integration degree of the module, and greatly reduces the packaging volume of the module.

[0020] (2) The RF modulation component proposed by the present invention is designed with a microwave attenuator and a low-noise amplifier, which can not only protect the laser chip from being damaged by high-power microwave signals, but also match the amplitude consistency of each channel microwave signal by adjusting the gain. At the same time, a detection circuit with a feedback function composed of a splitter and a detector is also designed, which can not only monitor the microwave characteristics, but also effectively improve the gain of the link system and improve the output signal-to-noise ratio of the signal.

[0021] (3) The present invention integrates and packages the laser component and the wavelength division multiplexing component, eliminates the operations of fiber fusion and fiber coiling of the module, greatly reduces the packaging size, and at the same time avoids the inconsistency of the optical power and wavelength of multiple channels, improving the environmental stability and reliability of the module.

[0022] (4) The wavelength division multiplexing component proposed by the present invention can flexibly match different channel integration quantities, and can meet the wavelength division multiplexing requirements of different wavelength intervals through the filter design.

[0023] (5) The wavelength division multiplexing component proposed by the present invention is designed with a steering prism structure and has an optical path pitch conversion function, which can convert the multi-channel optical paths with large and unequal intervals into multi-channel optical paths with small and equal intervals, and can meet the multiplexing of multi-channel optical paths with large intervals without increasing the packaging length of the module.

[0024] (6) The wavelength division multiplexing component proposed by the present invention is designed with a shielding absorber structure, which can effectively absorb the electromagnetic fields radiated and leaked by each channel RF modulation component along the channel direction of the shell, prevent its oscillation inside the module, reduce the electromagnetic interference between channels, and improve the electromagnetic shielding efficiency of the module. Description of the Drawings

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for use in the embodiments of the present invention. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0026] Figure 1 It is a schematic diagram of the principle of an analog optical transmission module integrating multi-channel wavelength division multiplexing provided by an embodiment of the present invention;

[0027] Figure 2 It is an assembly schematic diagram of an analog optical transmission module integrating multi-channel wavelength division multiplexing provided by an embodiment of the present invention;

[0028] Figure 3 It is a schematic diagram of the structure of a radio frequency modulation component provided by an embodiment of the present invention;

[0029] Figure 4 It is another schematic diagram of the structure of a radio frequency modulation component provided by an embodiment of the present invention;

[0030] Figure 5 It is a schematic diagram of the structure of a laser component provided by an embodiment of the present invention;

[0031] Figure 6 It is a schematic diagram of the structure of a four-channel equally spaced wavelength division multiplexing component provided by an embodiment of the present invention;

[0032] Figure 7 It is another layout schematic diagram of a shielding absorber provided by an embodiment of the present invention;

[0033] Figure 8 It is a schematic diagram of two end faces of a shielding absorber provided by an embodiment of the present invention;

[0034] Figure 9 It is a schematic diagram of the structure of a five-channel unequally spaced wavelength division multiplexing component provided by an embodiment of the present invention. Detailed implementation manners

[0035] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following further elaborates on the present invention in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] It should be noted that in the embodiments of the present application, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a method or device including a series of elements not only includes the clearly recorded elements, but also includes other elements not explicitly listed, or also includes elements inherent to the implementation of the method or device. Without more limitations, the elements defined by the statement "including..." do not exclude the existence of other related elements in the method or device including such elements (such as steps in the method or units in the device, and the units can be partial circuits, partial processors, partial programs or software, etc.).

[0037] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other, and the order of the steps can also be adjusted in a logical and non-conflicting manner. The present invention will be described in detail below with reference to the drawings and embodiments.

[0038] Embodiment 1:

[0039] As Figure 1 shown, referring to Figure 2 , in order to improve the integration of the analog optical emission module, reduce the module packaging volume and cost, and further improve the module reliability and environmental adaptability, Embodiment 1 of the present invention provides an analog optical emission module integrating multi-channel wavelength division multiplexing, including a radio frequency modulation component 1, a laser component 2, a laser control circuit 3, a wavelength division multiplexing component 4, and a packaging housing 5. Among them, the radio frequency modulation component 1 is used to process and transmit analog microwave signals, and load the analog microwave signals onto the laser component 2; the laser component 2 is used to realize the electro-optical conversion of analog microwave signals into optical signals and beam shaping; the laser control circuit 3 is used to provide constant current and constant temperature control for the laser component 2 (not shown in the figure, and its design and control principle are prior art and will not be elaborated here); the wavelength division multiplexing component 4 is used to multiplex the combined waves of optical signals of multiple different wavelength channels into one path; the packaging housing 5 is used to realize the integrated packaging of the radio frequency modulation component 1, the laser component 2, the laser control circuit 3, and the wavelength division multiplexing component 4.

[0040] Referring to Figure 1 、 Figure 2 , in a preferred solution of this embodiment, the analog optical emission module integrating multi-channel wavelength division multiplexing of this embodiment further includes a radio frequency connector 8, a tail tube 6, and an output optical fiber 7. The radio frequency connector 8 accesses the analog microwave signal into the optical emission module. After the radio frequency modulation component 1, the laser component 2, the laser control circuit 3, and the wavelength division multiplexing component 4 in the optical emission module process the analog microwave signal, the optical signals of multiple channels are combined into one path and coupled into the output optical fiber 7.

[0041] Reference Figure 1 In a preferred solution of this embodiment, there are four of each of the RF connector 8, the RF modulation component 1, and the laser component 2; and one each of the wavelength division multiplexing component 4 and the laser control circuit 3. With the above settings, there will be optical signals in four channels, and the wavelength division multiplexing component 4 will finally combine the optical signals in the four channels into one and couple them into the output optical fiber 7. In other embodiments, the numbers of the RF connector 8, the RF modulation component 1, the laser component 2, the wavelength division multiplexing component 4, and the laser control circuit 3 can also be set according to actual situations, and specific limitations are not made here.

[0042] Reference Figure 2 In a preferred solution of this embodiment, the packaging housing 5 includes a box body 51, a box inner cavity 52, a box outer cavity 53, an upper cover plate 54 of the box inner cavity, and a lower cover plate 55 of the box outer cavity. Specifically: the RF connector 8 is sintered at one end of the box body 51, the tail tube 6 is sintered at the other end of the box body 51, the RF modulation component 1, the laser component 2, and the wavelength division multiplexing component 4 are sequentially packaged on the base of the box inner cavity 52, the laser control circuit 3 is packaged in the groove of the box outer cavity 53, the upper cover plate 54 of the box inner cavity is packaged on the upper surface of the box inner cavity 52, and the lower cover plate 55 of the box outer cavity is fixed on the lower surface of the box outer cavity 53; after the multi-channel optical signals are multiplexed by the wavelength division multiplexing component 4, they are coupled to the output optical fiber 7, and the coupling end of the output optical fiber 7 is fixed in the tail tube 6. Under the above settings, the upper cover plate 54 of the box inner cavity realizes the airtight packaging of the internal RF and optical path components of the module, and the lower cover plate 55 of the box outer cavity realizes the protection of the module control circuit.

[0043] Reference Figure 3, in a preferred solution of this embodiment, a radio frequency modulation component is provided. The radio frequency modulation component 1 of this solution includes a microwave transmission line 11, a fixed attenuator 12, and a low noise amplifier 13. Among them, microwave transmission lines 11 are respectively arranged at the input end and the output end. The analog microwave signal is transmitted in the radio frequency modulation component 1 through the microwave transmission line 11 at the input end, and after passing through the fixed attenuator 12 and the low noise amplifier 13 in sequence, it is then loaded onto the laser component 2 through the microwave transmission line 11 at the output end. In this preferred solution, the fixed attenuator 12 has the characteristic of having multiple selectable attenuation values, and different gain values can be selected according to the differences in the output optical powers of the four channels of the optical module to match the output characteristics of each channel of the optical module. The low noise amplifier 13 amplifies the microwave signal and then loads it onto the laser component 2 through the microwave transmission line 11. During this process, the coplanar packaging of the independent microwave chip greatly improves the integration of the microwave modulation circuit and compresses the packaging space of the microwave circuit.

[0044] Reference Figure 4 , in another preferred solution of this embodiment, another radio frequency modulation component is provided. The radio frequency modulation component 1 of this solution includes a microwave transmission line 11, a variable attenuator 14, a low noise amplifier 13, a splitter 15, and a detector 16. Specifically, the variable attenuator 14 has the function of adjustable gain value. The analog microwave signal is transmitted in the radio frequency modulation component 1 through the microwave transmission line 11 at the input end, and after passing through the variable attenuator 14 and the low noise amplifier 13 in sequence, it is divided into two signals by the splitter 15. Among them, a part of the analog microwave signal (for example, more than 95% of the analog microwave signal) continues to be transmitted along the transmission arm of the splitter 15 and is loaded onto the laser component 2 through the microwave transmission line 11 at the output end. The remaining part of the analog microwave signal is coupled to the detector 16 through the coupling arm of the splitter 15, so that the main control board adjusts the control voltage according to the microwave signal detected by the detector 16 and changes the gain value of the variable attenuator 14. The radio frequency modulation component 1 proposed in this preferred solution can adjust the amplitude consistency of the microwave signal loaded onto the laser component 2, effectively improving the gain of the link system while improving the output signal-to-noise ratio of the signal.

[0045] Reference Figure 5, in a preferred embodiment of the present embodiment, the laser assembly 2 includes a cooler 21, a heat sink 22, a transition block 23, a laser chip 24, a backlight detector 25, a thermistor 26, a collimating lens 27, and an optical isolator 28. Among them, the laser chip 24, the backlight detector 25, and the thermistor 26 are assembled on the transition block 23, the transition block 23, the collimating lens 27, and the optical isolator 28 are assembled on the heat sink 22, the heat sink 22 is assembled on the cooler 21, and the cooler 21, the thermistor 26, the backlight detector 25, and the laser control circuit 3 are combined to achieve constant temperature control and constant current control of the laser assembly 2. Preferably, the transition block 23 is made of a ceramic material with a high thermal conductivity and a coefficient of expansion close to that of the laser chip 24, which not only provides good heat dissipation but also reduces the stress on the laser chip 24; the collimating lens 27 and the optical isolator 28 are assembled on the cooler 41 together with the heat sink 22, which has the effect of a constant temperature environment and improves the reliability of the assembly.

[0046] In a preferred embodiment of the present embodiment, the wavelength division multiplexing component 4 includes a steering prism, a filter 41, a glass substrate 42, an anti-reflection film 43, and an anti-reflection film 44. The incident end face and the exit end face of the glass substrate 42 are designed with an inclined angle. There are multiple filters 41, which are sequentially assembled on the incident end face of the glass substrate 42 at a fixed interval. The anti-reflection film 43 and the anti-reflection film 44 are assembled on the exit end face of the glass substrate 42. The wavelength division multiplexing component 4 further includes a spacer 45. The glass substrate 42 and the steering prism are fixed on the spacer 45. The anti-reflection film 44 is assembled on the acute angle side of the exit end face of the glass substrate 42, and the anti-reflection film 43 is assembled on the obtuse angle side of the exit end face of the glass substrate 42. The length of the anti-reflection film 43 is greater than the length of the anti-reflection film 44. In an alternative embodiment, the anti-reflection film 44 is arranged at the light-emitting position of the glass substrate 42, and the anti-reflection film 43 is arranged at the remaining positions. There are multiple steering prisms, which respectively horizontally deflect the light beams passing through them, and convert multiple channel light beams with unequal intervals or large intervals into multi-channel light beams with smaller and equal intervals.

[0047] Reference Figure 6, in a preferred solution of this embodiment, a four-channel equally-spaced wavelength division multiplexing component is provided. In this solution, the steering prism includes a first steering prism 46, a second steering prism 47, and a third steering prism 48. During use, the three beams of the first channel, the second channel, and the third channel respectively pass through the first steering prism 46, the second steering prism 47, and the third steering prism 48, and then form a four-channel parallel beam with a smaller channel interval together with the reference beam of the fourth channel, realizing the pitch conversion from a large channel interval to a small channel interval. Then, multiplexing processing is performed, which can significantly reduce the wavelength division multiplexing packaging space. Further, corresponding to the four channels, there are also four filter films (a first filter film, a second filter film, a third filter film, and a fourth filter film), and they are sequentially and equally-spaced parallelly pasted on the incident end face of the glass substrate 42 to transmit and reflect the optical signals of different wavelengths of the four channels. Combining with the high-reflection film 43 and the anti-reflection film 44 on the exit end face of the glass substrate 42, the multiplexing function of the four-channel beam is jointly realized. Under the above settings, specifically: After the first-channel beam passes through the first steering prism 46, it successively passes through the filter film 41 (the first filter film) and the glass substrate 42, and then exits from the anti-reflection film 44; After the second-channel beam passes through the second steering prism 47, it enters through the filter film 41 (the second filter film), propagates three times in the glass substrate 42, and then exits from the anti-reflection film 44 (After the second-channel beam passes through the second steering prism 47, it passes through the second filter film and the glass substrate 42, and then is reflected by the high-reflection film 43. After passing through the glass substrate 42 again, it is reflected by the first filter film. After passing through the glass substrate 42 for the third time, it exits from the anti-reflection film 44. The propagation principles of the subsequent third and fourth-channel beams are the same, only the number of reflections is different, so they will not be elaborated); By analogy, after the third-channel beam passes through the third steering prism 48, it enters through the filter film 41 (the third filter film), propagates five times in the glass substrate 42, and then exits from the anti-reflection film 44; The fourth-channel beam directly enters the filter film 41 (the fourth filter film), then propagates seven times in the glass substrate 42, and then exits from the anti-reflection film 44; The four-channel beams are combined and output at the anti-reflection film 44. The wavelength division multiplexing component 4 proposed in this solution can match the multiplexing requirements of different wavelength intervals by adjusting the coating characteristics of the filter film 41, and realizes the optical path matching of the optical signals of the four channels by reasonably arranging the positions of the steering prism and the glass substrate 42, improving the output-end power consistency.

[0048] In the above solution of the four-channel equally-spaced wavelength division multiplexing component, the present embodiment further provides a shielding absorber, which is used to absorb the electromagnetic fields radiated by the radio frequency modulation components (1) of each channel, can effectively reduce the electromagnetic crosstalk between channels, reduce the mutual electromagnetic interference inside the module of the present invention, and improve the electromagnetic shielding efficiency. The shielding absorber is fixed on the spacer 45. Refer to Figure 6 , a structure of the shielding absorber is as shown in Figure 6 Figure 100-1, which is arranged in the blank space at the upper right corner of the spacer 45 of the wavelength division multiplexing component 4, and can effectively utilize the space of the wavelength division multiplexing component. Another structure of the shielding absorber is as shown in Figure 7 Figure 100-2, and a shielding absorber is arranged at the incident position of each channel to absorb and process the electromagnetic field signals of each channel respectively. The end faces of the two shielding absorber structures are as shown in Figure 8 Figure 100-1. The absorber is a solid structure and has a good absorption effect on the electromagnetic field; while the absorber of 100-2 is a hollow structure, and under the condition of not blocking the optical path, it can fully absorb the electromagnetic radiation of the corresponding channel.

[0049] Furthermore, in the wavelength division multiplexing solution provided by this preferred embodiment, all wavelength division elements are integrated on the spacer 45, which is convenient for assembly and repair, improves production efficiency, and reduces packaging costs. Preferably, the filter 41 is fixed on the glass substrate 42 at an equal interval of 2 mm. Preferably, the inclination angles of the incident end face and the exit end face of the glass substrate 42 are 13.5°.

[0050] Refer to Figure 9 , in another preferred solution of the present embodiment, a five-channel non-equally-spaced wavelength division multiplexing component is further provided. In this solution, the turning prism includes a fourth turning prism 49, a fifth turning prism 410, a sixth turning prism 411, and a seventh turning prism 412. After the four non-equally-spaced light beams of the first channel, the second channel, the fourth channel, and the fifth channel respectively pass through the fourth turning prism 49, the fifth turning prism 410, the sixth turning prism 411, and the seventh turning prism 412, they form five equally-spaced parallel light beams with a smaller channel interval together with the reference light beam of the third channel, so as to realize the pitch conversion of multi-channel light beams with a larger and unequal interval to multi-channel light beams with a smaller and equal interval, and then the multiplexing function is realized through the filter 41, the glass substrate 42, the high-reflection film 43, and the anti-reflection film 44. Specifically, the reflection principle of the light beam in the glass substrate 42 in this solution is the same as that of the previous four channels, and will not be elaborated here. The wavelength division multiplexing solution provided by the present embodiment greatly reduces the packaging size of the wavelength division multiplexing and improves the module integration degree by adjusting the selection of the reference optical path and adjusting the length and layout of each turning prism. A shielding absorber can also be provided in the above five-channel non-equally-spaced wavelength division multiplexing component, as shown in Figure 9As shown in Fig. 100-3, the shielding absorber in this solution is arranged in front of or behind the turning prism, and the optical path passes by its side to eliminate the electromagnetic influence between channels.

[0051] In summary, the analog light source module integrating multi-channel wavelength division multiplexing proposed by the present invention realizes the integrated packaging of the radio frequency modulation component, the laser component, the wavelength division multiplexing component and the control circuit, significantly improves the packaging integration degree of the module, and greatly reduces the packaging volume of the module. The radio frequency modulation component proposed by the present invention is designed with a microwave attenuator and a low noise amplifier, which can not only protect the laser chip from being damaged by high-power microwave signals, but also match the amplitude consistency of microwave signals in each channel by adjusting the gain. At the same time, a detection circuit with a feedback function composed of a splitter and a detector is also designed, which can not only monitor the microwave characteristics, but also effectively improve the gain of the link system and improve the output signal-to-noise ratio of the signal. The present invention integrates the laser component and the wavelength division multiplexing component for packaging, eliminates the operations of fiber fusion and fiber coiling of the module, greatly reduces the packaging size, and at the same time avoids the inconsistency of optical power and wavelength in multiple channels, improving the environmental stability and reliability of the module. The wavelength division multiplexing component proposed by the present invention can flexibly match different channel integration numbers, and can meet the wavelength division multiplexing requirements with different wavelength intervals through the filter design. The wavelength division multiplexing component proposed by the present invention is designed with a turning prism structure, which has the function of optical path pitch conversion, and can convert multi-channel optical paths with large and unequal intervals into multi-channel optical paths with small and equal intervals, and can meet the multiplexing of multi-channel optical paths with large intervals without increasing the packaging length of the module. The wavelength division multiplexing component proposed by the present invention is designed with a shielding absorber structure, which can effectively absorb the electromagnetic fields radiated and leaked by the radio frequency modulation components in each channel along the housing channel direction, prevent its oscillation inside the module, reduce the electromagnetic interference between channels, and improve the electromagnetic shielding efficiency of the module.

[0052] Although the specific embodiments of the present invention are described above in conjunction with the drawings, the present invention is not limited to the above specific embodiments. The above specific embodiments are only illustrative and not restrictive. For example, according to actual usage requirements, the radio frequency modulation circuit can use an attenuator or can cancel the attenuator, can have a feedback modulation function or can not have a feedback modulation function; the wavelength division multiplexing component can be an even number of channels or an odd number of channels, can be equal channel intervals or unequal channel intervals, the element for turning the optical path can be a turning prism or a plane mirror, and the inclined angle of the glass substrate can be 13.5 degrees, 10° or other angles.

[0053] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention. The content not described in detail in this specification belongs to the prior art well known to those skilled in the art.

Claims

1. An analog optical emission module integrating multi-channel wavelength division multiplexing, characterized in that, It includes a plurality of radio frequency modulation components (1), a plurality of laser components (2), a laser control circuit (3), a wavelength division multiplexing component (4), and a packaging housing (5). Among them, the radio frequency modulation component (1) is used to process and transmit an analog microwave signal, and load the analog microwave signal onto the laser component (2). One radio frequency modulation component (1) corresponds to one laser component (2) to load the analog microwave signal onto the corresponding laser component (2); the laser component (2) is used to realize the electro-optic conversion of the analog microwave signal to an optical signal and beam shaping; the laser control circuit (3) is used to provide constant current and constant temperature control for each laser component (2); the wavelength division multiplexing component (4) is used to multiplex the combined waves of optical signals in multiple different wavelength channels into one path; the packaging housing (5) is used to realize the integrated packaging of the plurality of radio frequency modulation components (1), the plurality of laser components (2), the laser control circuit (3), and the wavelength division multiplexing component (4). The radio frequency modulation component (1) includes a microwave transmission line (11), a variable attenuator (14), a low noise amplifier (13), a splitter (15), and a detector (16). The analog microwave signal is transmitted within the radio frequency modulation component (1) through the microwave transmission line (11) at the input end, and after passing through the variable attenuator (14) and the low noise amplifier (13) in sequence, it is split into two signals by the splitter (15). Among them, a part of the analog microwave signal continues to be transmitted along the transmission arm of the splitter (15) and is loaded onto the laser component (2) through the microwave transmission line (11) at the output end. The remaining part of the analog microwave signal is coupled to the detector (16) through the coupling arm of the splitter (15), so that the main control board adjusts the control voltage according to the microwave signal detected by the detector (16) and changes the gain value of the variable attenuator (14); the radio frequency modulation component (1) can adjust the amplitude consistency of the microwave signal loaded onto the laser component (2). The wavelength division multiplexing component (4) includes a shielding absorber, and the shielding absorber is used to absorb the electromagnetic fields radiated by the radio frequency modulation components (1) in each channel. A shielding absorber is provided at the incident point of each channel to absorb and process the electromagnetic field signals of each channel respectively.

2. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 1, characterized in that, The laser component (2) includes a cooler (21), a heat sink (22), a transition block (23), a laser chip (24), a backlight detector (25), a thermistor (26), a collimating lens (27), and an optical isolator (28). Among them, the laser chip (24), the backlight detector (25), and the thermistor (26) are assembled on the transition block (23), the transition block (23), the collimating lens (27), and the optical isolator (28) are assembled on the heat sink (22), the heat sink (22) is assembled on the cooler (21), and the cooler (21), the thermistor (26), the backlight detector (25), and the laser control circuit (3) are combined to achieve constant temperature control and constant current control of the laser component (2).

3. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 1, characterized in that, The wavelength division multiplexing component (4) includes a steering prism, a filter (41), a glass substrate (42), an anti-reflection film (43), and an anti-reflection film (44). The incident end face and the exit end face of the glass substrate (42) are designed with an inclined angle. A plurality of filters (41) are arranged at fixed intervals on the incident end face of the glass substrate (42) in sequence, and the anti-reflection film (43) and the anti-reflection film (44) are assembled on the exit end face of the glass substrate (42).

4. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 3, characterized in that, The wavelength division multiplexing component (4) further includes a spacer block (45). The glass substrate (42), the steering prism, and the shielding absorber are fixed on the spacer block (45). The anti-reflection film (44) is assembled on the acute angle side of the exit end face of the glass substrate (42), and the anti-reflection film (43) is assembled on the obtuse angle side of the exit end face of the glass substrate (42).

5. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 3, characterized in that, A plurality of steering prisms are provided to horizontally deflect the light beams passing through them respectively, and convert multi-channel light beams with unequal intervals or large intervals into multi-channel light beams with smaller and equal intervals.

6. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 5, characterized in that, The steering prism includes a first steering prism (46), a second steering prism (47), and a third steering prism (48). After the first channel light beam passes through the first steering prism (46), it passes through the filter (41) and the glass substrate (42) in sequence, and then exits from the anti-reflection film (44). After the second channel light beam passes through the second steering prism (47), it enters through the filter (41), propagates three times in the glass substrate (42), and then exits through the anti-reflection film (44). After the third channel light beam passes through the third steering prism (48), it enters through the filter (41), propagates five times in the glass substrate (42), and then exits through the anti-reflection film (44). The fourth channel light beam directly enters the filter (41), then propagates seven times in the glass substrate (42), and then exits through the anti-reflection film (44). The four channel light beams are combined and output at the anti-reflection film (44).

7. The analog optical emission module integrating multi-channel wavelength division multiplexing according to claim 5, characterized in that, The turning prism includes a fourth turning prism (49), a fifth turning prism (410), a sixth turning prism (411), and a seventh turning prism (412). After the four non-equidistant light beams in the first channel, the second channel, the fourth channel, and the fifth channel respectively pass through the fourth turning prism (49), the fifth turning prism (410), the sixth turning prism (411), and the seventh turning prism (412), they form five equidistant parallel light beams with a smaller channel interval together with the reference light beam in the third channel, so as to realize the conversion from multi-channel light beams with a larger and unequal interval to multi-channel light beams with a smaller and equal interval. Then, the multiplexing function is realized through the filter (41), the glass substrate (42), the high-reflection film (43), and the anti-reflection film (44).

8. The analog optical emission module integrating multi-channel wavelength division multiplexing according to any one of claims 1-7, characterized in that, It further includes a plurality of RF connectors (8), a tail tube (6), and an output optical fiber (7). The packaging housing (5) includes a box body (51), a box inner cavity (52), a box outer cavity (53), an upper cover plate of the box inner cavity (54), and a lower cover plate of the box outer cavity (55). Among them, one RF connector (8) corresponds to one RF modulation component (1). Specifically: A plurality of the RF connectors (8) are sintered at one end of the box body (51), the tail tube (6) is sintered at the other end of the box body (51), a plurality of the RF modulation components (1), a plurality of the laser assemblies (2), and the wavelength division multiplexing component (4) are sequentially packaged on the base of the box inner cavity (52), the laser control circuit (3) is packaged in the groove of the box outer cavity (53), the upper cover plate of the box inner cavity (54) is packaged on the upper surface of the box inner cavity (52), and the lower cover plate of the box outer cavity (55) is fixed on the lower surface of the box outer cavity (53); after the multi-channel optical signals are multiplexed by the wavelength division multiplexing component (4), they are coupled to the output optical fiber (7), and the coupling end of the output optical fiber (7) is fixed in the tail tube (6).

Images