A 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system

Abstract

The utility model belongs to 5G communication technical field, concretely relates to a kind of 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system, including the BBU being arranged in machine room, BBU is electrically connected with corresponding optical transceiver unit I, optical transceiver unit I is connected with multiple indoor optical transceiver unit II by optical fiber and corresponding optical branching unit, optical transceiver unit II is electrically connected with corresponding antenna array, the optical transceiver unit I, optical transceiver unit II all include optical transmitting unit, optical receiving unit.The utility model has realized that the uplink and downlink signal of existing millimeter wave base station can satisfy the demand of remote coverage by the method of optical transmission, verifies and designs the radio frequency optical transmission scheme and product implementation of 24GHz~28GHz, realizes the remote of optical transceiver unit by optical external modulation technology, and greatly reduces size, meets the equipment requirement of small volume, light weight.

Description

TECHNICAL FIELD

[0001] The utility model belongs to 5G communication technical field, specifically relates to a kind of 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system. BACKGROUND

[0002] According to the provisions of 3GPP 38.101 protocol, 5G NR mainly uses two frequency bands-FR1 and FR2: FR1 (450MHz~6GHz), namely the so-called Sub 6GHz;FR2 (24.25GHz~52.6GHz), namely the so-called 5G millimeter wave frequency band.The evolution of FR1 is considered by many people as the evolution of the current 4G system, while the expansion of millimeter wave is the biggest innovation and difficulty of the current 5G communication system, because even the Massivemultiple-input multiple-output (Massive MIMO) technology is more to compensate for the defects of millimeter wave frequency band.

[0003] Due to the low loss, ultra bandwidth and high shielding characteristics of the optical fiber system transmission, combined with the advantages of high frequency, large bandwidth and good stability of the microwave photoelectric assembly, the low loss and long distance transmission of radio frequency signal in the n258 frequency band (TDD uplink / downlink: 24.25GHz~27.5GHz) of FR2 of 5G communication is realized.

[0004] Compared with the FR1 (450MHz~6GHz) frequency band of 5G communication, the FR2 frequency band has short wavelength and weak coverage ability (short coverage distance) and weak diffraction ability, but since FR2 is a high frequency band, it supports a maximum bandwidth of 400MHz, which is much higher than the 100MHz bandwidth of FR1.The characteristics of millimeter wave signal propagation are summarized as follows:

[0005] 1) High free space path loss: millimeter wave has high frequency, and the propagation loss in air is large, which leads to rapid weakening of signal strength, especially for long distance transmission;

[0006] 2) Easy to be blocked: millimeter wave has short wavelength, which makes it difficult to achieve extensive network coverage, which is a challenge for large-scale communication network construction;

[0007] 3) Short coverage distance: millimeter wave has relatively short coverage distance, which makes it difficult to achieve extensive network coverage, which is a challenge for large-scale communication network construction.

[0008] 4) Significant atmospheric attenuation: in atmospheric propagation, millimeter wave will be absorbed by water vapor, oxygen and other components in the atmosphere, resulting in serious signal attenuation, especially under severe weather conditions.

[0009] 5) Requires straight-line propagation: millimeter wave transmission requires straight-line propagation and cannot effectively bypass obstacles, which limits its application in complex environments;

[0010] 6) High equipment cost: due to the high requirements of millimeter wave technology on equipment, including high-performance antennas and processors, the cost of related equipment is also high; due to poor coverage, more base stations are needed to meet coverage, resulting in a sharp increase in construction cost. Practical new type content

[0011] To solve the above technical problems, the utility model provides a kind of 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system.

[0012] The utility model discloses a kind of 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system according to the utility model, including the BBU being set in machine room, BBU is electrically connected with corresponding optical transceiver unit I, optical transceiver unit I is connected with multiple indoor optical transceiver unit II by optical fiber and corresponding optical branching filter, optical transceiver unit II is electrically connected with corresponding antenna array, the optical transceiver unit I, optical transceiver unit II all include optical transmitting unit, optical receiving unit.

[0013] Further, the optical transmitting unit includes a TYPEC power supply board and interface for power supply, a high-power light source, an optical source optical power control board provided with an automatic power control circuit, an optical source temperature control board provided with an automatic temperature control circuit, an external modulator for modulating the optical power of the high-power light source, and an external modulator bias plate for controlling the bias voltage of the external modulator.

[0014] Further, the optical receiving unit includes a TYPEC power supply board for power supply and a photodetector, and the photodetector includes a radio frequency amplifier.

[0015] Further, the optical transceiver unit I and the BBU are co-rack arranged.

[0016] Further, the optical transceiver unit II and the antenna array are co-cabinet arranged.

[0017] Further, the optical transmitting unit and the optical receiving unit are electrically connected with the corresponding BBU or antenna array through an SMA radio frequency port.

[0018] Further, the optical branching filter is a PLC planar waveguide type optical branching filter.

[0019] Further, the optical fiber is a zero dispersion optical fiber.

[0020] Further, the BBU, optical transceiver unit I, optical branching filter and optical transceiver unit II are externally packaged in an aluminum alloy box, and internally provided with a lining.

[0021] Compared with the prior art, the present application has the advantages that:

[0022] The present application realizes that the uplink and downlink signals of the existing millimeter wave base station can meet the demand of remote coverage through optical transmission, verifies and designs a 24GHz-28GHz radio frequency optical transmission scheme and product implementation, realizes the remote extension of the optical transceiver unit through optical external modulation technology, greatly reduces the size, and meets the requirements of small size and light weight.

[0023] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, the content of the specification can be implemented, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are described in detail, and the accompanying drawings are as follows. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The optical transmission link schematic diagram of 5G millimeter wave indoor coverage in the embodiment of the present application;

[0025] Figure 2 The function schematic diagram of the optical transceiver unit in the optical transmission link in the embodiment of the present application;

[0026] Figure 3 The internal layout schematic diagram of the optical transmitting unit in the embodiment of the present application; Figure 2

[0027] Figure 4 The internal layout schematic diagram of the optical receiving unit in the embodiment of the present application; Figure 2

[0028] The external modulation circuit schematic diagram of the millimeter wave signal optical transmission in the embodiment of the present application; Figure 5 Figure 3 The schematic diagram of the PLC planar waveguide type optical branching device in the embodiment of the present application;

[0029] Figure 6a The side view of the PLC optical branching transmission link in the embodiment of the present application;

[0030] Figure 6b Figure 6a The schematic diagram of the PLC optical branching transmission link in the embodiment of the present application;

[0031] Figure 6c The schematic diagram of the PLC optical branching transmission link in the embodiment of the present application.

[0032] REFERENCE SIGNS

[0033] 1- machine room;

[0034] 2- indoor;

[0035] 3- BBU;​​​

[0036] 4 - Light emitting unit I;

[0037] 5 - Light receiving unit I;

[0038] 6 - Optical fiber branching matrix;

[0039] 7 - Antenna array;

[0040] 8 - Light emitting unit II;

[0041] 9 - Light receiving unit II;

[0042] 10 - Optical transceiver unit II;

[0043] 11 - TYPE-C power supply board and interface;

[0044] 12 - High power light source;

[0045] 13 - Light source optical power control board;

[0046] 14 - Light source temperature control board;

[0047] 15 - External modulator bias board;

[0048] 16 - External modulator;

[0049] 17 - TYPE-C power supply board;

[0050] 18 - Photodetector;

[0051] 19 - Optical splitter;

[0052] 20 - Optical transceiver unit I. DETAILED DESCRIPTION

[0053] In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0055] It should be noted that similar reference numbers and characters refer to similar items in the following drawings, and once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0056] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the application is used, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0057] In addition, the terms "horizontal", "vertical", "overhanging", and the like do not mean that the component must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0058] In the description of the present application, it should also be noted that unless otherwise explicitly specified and limited, the terms "provided", "mounted", "connected", "connected" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0059] In the present application, unless otherwise explicitly specified and limited, the first feature "above" or "below" the second feature can include the first and second features directly contacting, or the first and second features not directly contacting but contacting through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature includes the first feature directly above and obliquely above the second feature, or only means that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature includes the first feature directly below and obliquely below the second feature, or only means that the horizontal height of the first feature is less than that of the second feature.

[0060] The features and performance of the present application suitable for a 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system are further described in detail below in conjunction with the embodiments.

[0061] The utility model discloses a 5G communication FR2 millimeter wave band indoor ultra -micro base station radio frequency remote system's embodiment one, as shown in formula Figures 1 to 6b Below, the system is briefly called.

[0062] As shown in Figure 1 And Figure 2 The system is used to set up in machine room 1 and indoor 2, and machine room 1 sets up BBU (baseband processing unit) 3 and optical transceiver unit matrix, and the optical transceiver unit matrix includes a plurality of optical transceiver unit I (TRU) 20, and the optical transceiver unit I 20 includes optical transmitting unit I 4, optical receiving unit I 5, and the optical transceiver unit I 20 is set up with BBU 3 in rack.

[0063] The optical transceiver unit I 20 is communicated and connected with each AAU in the indoor through corresponding optical fiber distribution matrix 6, and the AAU in the indoor includes optical transceiver unit II (TRU) 10 and antenna array 7, and the optical transceiver unit II 10 includes optical transmitting unit II 8 and optical receiving unit II 9. The optical transmitting unit I 4 passes through optical fiber and optical fiber distribution matrix 6 and transmits optical signal to optical receiving unit II 9, and the optical transmitting unit II 8 passes through optical fiber and optical fiber distribution matrix 6 and transmits optical signal to optical receiving unit I 5. In the AAU, the optical transceiver unit II 10 and the antenna array 7 are in the same machine box, and the AAU is arranged on the indoor roof, and the vertical radiation reaches 20-35 meters.

[0064] The optical transceiver unit I 10 in the machine room and the optical transceiver unit II 20 in the roof AAU are the same structure, and all include optical transmitting unit, optical receiving unit. The optical transmitting unit includes TYPEC power board and interface 11, high-power light source 12, light source optical power control board 13, light source temperature control board 14, external modulator bias board 15 and external modulator 16, as shown in Figure 3 The optical transmitting unit modulates millimeter wave signal onto optical signal and transmits through optical fiber.

[0065] The high-power light source 12 adopts narrow-line-width high-power light source (laser), and the light source optical power control board 13 is provided with an automatic power control circuit (APC, Auto Power Control), and the light source temperature control board 14 is provided with an automatic temperature control circuit (ATC, Auto Temperature Control), and the external modulator 16 adopts a 40G external modulator. Taking the laser as the core, cooperating with the circuit design of external APC and ATC, the power stability, wavelength stability and the like of the laser can be better guaranteed, and continuous light output is realized. Then the millimeter wave signal (radio frequency signal) is modulated onto the optical signal through the external modulator 16. The external modulation principle is that the laser outputs constant optical power to the external modulator 16, and the radio frequency signal controls the external modulator 16 to change the output optical power, so as to realize modulation, as shown in Figure 5The outer modulator bias plate 15 is used for controlling the bias voltage of the outer modulator 16, and ensuring the stability of the bias voltage.

[0066] After the control technology of the laser power and wavelength stability is adopted, the laser can have sufficient stability control ability at the limit working temperature of -40 DEG C to +70 DEG C, the wavelength temperature drift is controlled within ±0.15 nm, and the maximum fluctuation of the optical power is less than 0.2 dB.

[0067] The optical transmitting unit I 4 converts the millimeter wave signal processed by the BBU 3 into an optical signal, and transmits the optical signal to the optical receiving unit II 9 through the optical fiber distribution matrix 6.

[0068] The optical receiving unit includes a TYPEC power supply plate 17 and a photodetector 18. The photodetector 18 adopts a 40G photodetector, and the 40G photodetector contains a radio frequency amplifier, so that the overall design of the photoelectric conversion part and the radio frequency amplification part is realized. The optical receiving unit I 5 in the machine room 1 receives the optical signal, and the photodetector 18 is used to realize demodulation, photoelectric conversion and amplification, and then the processed signal is transmitted to the BBU 3 for processing.

[0069] The optical transmitting unit and the optical receiving unit adopt TYPEC power supply.

[0070] The optical transmitting unit and the optical receiving unit adopt SMA radio frequency ports and corresponding equipment electrical connection.

[0071] The optical fiber distribution matrix 6 comprises a plurality of optical splitters 19, and the optical splitters 19 adopt PLC planar waveguide type optical splitters (PLC Sp1itter) which are quartz substrate-based integrated waveguide optical power distribution devices, and the optical splitter network system couples, branches and distributes optical signals for transmission, like the coaxial cable transmission system. Figures 6a to 6b

[0072] The optical transmitting unit I 4 in the machine room 1 sends an optical signal to a corresponding optical splitter 19 in the optical fiber distribution matrix 6, and the optical splitter 19 divides the optical signal into a plurality of paths and transmits the optical signal to a corresponding optical receiving unit II 9 in the room. After the optical transmitting unit II 8 of the AAU sends an optical signal, the optical signal is transmitted to the optical receiving unit I 5 in the machine room through the corresponding optical splitter 19, and is collected into the BBU 3 after photoelectric conversion for processing.

[0073] The optical splitters 19 are connected with the optical transceiver units I 20 and the optical transceiver units II 10 through optical fibers, and the optical fibers of the utility model adopt zero dispersion optical fibers. The optical wavelength of the optical signal of the utility model is 1550nm window, and the typical value of the attenuation coefficient is 0.2dB / Km. The commonly used G652D optical fiber in the prior art belongs to a non-dispersion-shifted optical fiber, and the zero dispersion wavelength is near 1310nm, which has a significant dispersion effect on the 1550nm wavelength, especially in the case of long-distance transmission. Dispersion mainly broadens the time-domain optical pulse signal, reduces the signal quality, causes the waveform of the analog signal to be broadened, and specifically, the envelope of the optical carrier is distorted, and after detection by the optical detector, the second-order distortion of the electrical signal is mainly shown. At present, dispersion compensation technology is mainly used to cope with the dispersion effect in long-distance optical fiber transmission, and the utility model adds dispersion compensation optical fibers in the optical fiber delay line to offset the dispersion effect of the G.652D optical fiber, thereby forming a zero dispersion optical fiber. The millimeter wave signal passes through the zero dispersion optical fiber, and low-loss and long-distance transmission can be realized, and the requirements of indoor vertical direction and unobstructed coverage of the millimeter wave signal can be met.

[0074] By combining the zero dispersion optical fiber and the optical splitter, the modulated optical signal can be reasonably distributed to each indoor AAU, so that the uniform distribution of the optical signal is realized, the dispersion of the millimeter wave signal in long-distance optical fiber transmission is greatly reduced, the quality requirements of signal transmission are met, and the minimum loss of optical transmission is ensured.

[0075] The utility model adopts an aluminum alloy packaging box to package each device (BBU3, optical transceiver unit I 20, optical splitter 19 and optical transceiver unit II 10), and the inside is protected by lining, the product has moisture-proof and anti-vibration measures, and the product is convenient to carry and carry. ​

[0076] The utility model has the characteristics of ultra-low loss, large bandwidth and high reliability, meets the urgent needs of the existing millimeter wave base station indoor distribution, and can provide large bandwidth, large capacity and low delay communication guarantee in the field of hospital telemedicine.

[0077] According to the technical disadvantages of the current 5G millimeter wave promotion, the main problem is that the weather has a great influence, and the path loss exceeds the use requirements. Therefore, the initial indoor distribution of 5G millimeter wave should become the mainstream (80% of the largest 5G communication flow occurs indoors). For example Figure 1 As shown in the scene, the antenna signal propagation of the utility model is almost straight, the path length is usually between 5m-35m, and the weather factor has zero interference. Especially in the hospital (in the operating room, remote medical scene), deep mining area below the ground, high-speed rail station, airport waiting room, etc. The area affected by the weather is very small, and it can be widely used.

[0078] The utility model realizes that the uplink and downlink signals of the existing millimeter wave base station can meet the demand of remote coverage through optical transmission, verifies and designs the 24GHz-28GHz radio frequency optical transmission scheme and product implementation, realizes the remote distance of the optical transceiver unit through the optical external modulation technology, greatly reduces the size, and meets the equipment requirements of small size and light weight.

[0079] The second embodiment of the 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system of the utility model can continue to send the multiple optical signals branched by the optical splitter 19 to the corresponding optical splitter 19, realize secondary light splitting, and further send the optical signals to more optical receiving units II 9, as shown in Figure 6c The optical splitters 19 are connected by optical fibers.

[0080] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A 5G communication FR2 millimeter wave band indoor ultra-micro base station radio frequency remote system, characterized in that: The application relates to a kind of optical transceiver units and BBU, comprising BBU (3) arranged in machine room (1), BBU (3) is electrically connected with corresponding optical transceiver unit I (20), optical transceiver unit I (20) is connected with multiple indoor optical transceiver unit II (10) by optical fiber and corresponding optical splitter (19), optical transceiver unit II (10) is electrically connected with corresponding antenna array (7), the optical transceiver unit I (20), optical transceiver unit II (10) all include optical transmitter unit, optical receiver unit. 2.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical transmitter unit includes TYPEC power supply board and interface (11) for power supply, high-power light source (12), light source optical power control board (13) arranged with automatic power control circuit, light source temperature control board (14) arranged with automatic temperature control circuit, external modulator (16) for modulating the optical power of high-power light source (12), external modulator bias plate (15) for controlling the bias voltage of external modulator (16). 3.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical receiver unit includes TYPEC power supply board (17) for power supply, photodetector (18), and the photodetector (18) includes a radio frequency amplifier. 4.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical transceiver unit I (20) is arranged in a rack with the BBU (3). 5.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical transceiver unit II (10) and the antenna array (7) are arranged in a cabinet. 6.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system according to claim 1, wherein: The optical transmitter unit and the optical receiver unit are electrically connected with the corresponding BBU (3) or antenna array (7) through an SMA radio frequency port. 7.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical splitter (19) is a PLC planar waveguide type optical splitter. 8.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The optical fiber is a zero dispersion optical fiber. 9.The 5G communication FR2 millimeter wave band indoor ultra-mini base station remote radio unit system of claim 1, wherein: The BBU (3), optical transceiver unit I (20), optical splitter (19), and optical transceiver unit II (10) are externally packaged in an aluminum alloy box and internally lined.

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