Passive distributed 5G micro base station system based on RoF

Abstract

The invention discloses a passive distributed 5G micro base station system based on RoF, and the system comprises a near-end base station which is used for processing a baseband signal and modulating the baseband signal to a light wave frequency band; and generate an energy signal; the multimode optical fiber is used for transmitting energy signals of the near-end base station and the far-end FEM; the single-mode optical fiber is used for transmitting radio frequency signals of the near-end base station and the far-end FEM; the far-end FEM is used for receiving the energy signal transmitted through the multimode optical fiber and converting the energy signal into electric energy for power supply; and receiving the optical signal transmitted through the single-mode optical fiber, and demodulating the optical signal into a radio frequency signal. According to the invention, the far-end FEM can realize long-distance, large-bandwidth and ultrahigh-information-density 5G signal coverage without external power supply.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular to a passive distributed 5G micro base station system based on RoF. Background Art

[0002] The main drawbacks of existing distributed base station systems include the need for external power supply for the radio remote unit and complex baseband signal processing, which results in bulky equipment architecture and high installation and maintenance costs. In addition, these systems use coaxial lines for signal transmission, which results in large path loss, especially at high frequencies, where signal attenuation is significant, limiting long-distance and wide-area coverage capabilities.

[0003] In addition, existing optical signal transmission systems have problems with energy transmission efficiency. Energy light easily interferes with signal light, resulting in reduced signal quality and stability. Although single-fiber optical signal transmission is simple, its energy signal density is low and cannot meet the needs of high-energy transmission. These technical defects make it difficult for existing systems to achieve high-bandwidth, high-speed and wide-area coverage 5G networks. Summary of the invention

[0004] According to one aspect of the present invention, a passive distributed 5G micro base station system based on RoF is provided, in which the remote FEM does not require external power supply to achieve long-distance, large-bandwidth, and ultra-high information density 5G signal coverage.

[0005] In order to solve the above technical problems, the first aspect of the present invention discloses a passive distributed 5G micro base station system based on RoF, comprising:

[0006] A near-end base station, for processing baseband signals, modulating the baseband signals to an optical wave frequency band, and generating energy signals;

[0007] Multimode optical fiber, used to transmit energy signals between the near-end base station and the far-end FEM;

[0008] Single-mode optical fiber, used to transmit radio frequency signals between the near-end base station and the far-end FEM;

[0009] The remote FEM is used to receive energy signals transmitted through the multi-mode optical fiber, convert the energy signals into electrical energy for power supply; receive optical signals transmitted through the single-mode optical fiber, and demodulate them into radio frequency signals.

[0010] In some embodiments, the remote FEM includes an optical demodulator, an optical modulator, a first remote power amplifier, a second remote power amplifier, a second low noise amplifier, a first low noise amplifier, a filter and a photovoltaic power supply; the optical demodulator is sequentially connected to the first remote power amplifier, the second remote amplifier, the filter, and the transmitting antenna; the optical modulator is sequentially connected to the second low noise amplifier, the first low noise amplifier, the filter, and the receiving antenna.

[0011] In some embodiments, the proximal base station includes a proximal RRU, an optical modulator, an optical demodulator, an attenuator and a circulator; the proximal RRU is connected to the first port of the circulator, the second port of the circulator is connected to the optical modulator through the attenuator, and the third port of the circulator is connected to the optical demodulator.

[0012] In some embodiments, the single-mode optical fiber includes a first single-mode optical fiber and a second single-mode optical fiber; the optical modulator of the proximal base station is connected to the optical demodulator of the remote FEM through the first single-mode optical fiber; the optical modulator of the remote FEM is connected to the optical demodulator of the proximal base station through the second single-mode optical fiber.

[0013] In some embodiments, during uplink signal transmission, the remote FEM receives the uplink signal and modulates it to an optical wave frequency band to form an optical carrier signal, and the optical carrier signal is transmitted to the near-end base station via the first single-mode optical fiber.

[0014] In some embodiments, during downlink signal transmission, a proximal base station receives a downlink signal and modulates it to an optical wave frequency band to form an optical carrier signal, which is transmitted to a remote FEM via a second single-mode optical fiber, and the remote FEM demodulates the optical carrier signal into a radio frequency signal.

[0015] In some embodiments, the proximal base station is further provided with a light emitter, which generates energy laser, and the energy laser is transmitted to the distal FEM via a multimode optical fiber.

[0016] In some embodiments, the optical demodulator or optical modulator is a RoF demodulator or RoF modulator with a temperature compensation function.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a passive distributed 5G micro base station system based on RoF. By adopting dual-fiber optical signal and energy simultaneous transmission technology, signals and energy are transmitted through single-mode optical fiber and multi-mode optical fiber respectively, realizing a passive design of remote FEM without external power supply, simplifying system layout, reducing installation and maintenance costs, and improving the signal isolation and transmission efficiency of the system. It is suitable for 5G network coverage with high information density and can provide stable and high-speed 5G communication services over long distances and over a large range. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the architecture of a RoF-based passive distributed 5G micro base station system provided by the present invention;

[0020] Figure 2 A schematic diagram of a downlink signal route of a passive distributed 5G micro base station system based on RoF provided by the present invention;

[0021] Figure 3 Another schematic diagram of the architecture of a RoF-based passive distributed 5G micro base station system provided by the present invention;

[0022] Figure 4 This is another schematic diagram of the architecture of a RoF-based passive distributed 5G micro base station system provided by the present invention;

[0023] Figure 5 A schematic diagram of downlink EVM test results of a passive distributed 5G micro base station system based on RoF provided by the present invention;

[0024] Figure 6 A schematic diagram of a downlink power test of a RoF-based passive distributed 5G micro base station system provided by the present invention. DETAILED DESCRIPTION

[0025] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The terms "including" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or modules is not necessarily limited to those steps or modules explicitly listed, but may include other steps or modules not explicitly listed or inherent to these processes, methods, products or apparatus.

[0027] An embodiment of the present invention discloses a passive distributed 5G micro base station system based on RoF (Radio-over-Fiber, optical wireless communication technology), in which the remote FEM (Front End Module) does not require external power supply to achieve long-distance, large-bandwidth, and ultra-high information density 5G signal coverage.

[0028] Traditionally, an empty carrier is generated at the near end for uplink return transmission, and one optical fiber is used for both transmission and reception. Both the near-end base station and the far-end FEM need to combine the transmit and receive optical signals and use an optical circulator to separate the transmit and receive signals. The transmit and receive isolation requirements are high, the structure is complex, and the cost is high. Based on this, the present application generates a tunable laser source for downlink transmission at the near-end base station, and then modulates the downlink RF signal to the optical frequency band, and transmits it to the far-end FEM through the first single-mode optical fiber; generates a tunable laser source for uplink return transmission at the far-end FEM, and then modulates the uplink signal to the optical frequency band, and transmits it back to the near-end base station through the second single-mode optical fiber, so as to realize full-duplex communication of the far-end 5G micro base station system; there is no need for optical signal combination and separation, and the transmit and receive optical signals are transmitted separately by different optical fibers, and an empty carrier is generated at the far end for uplink return transmission, which has high transmit and receive isolation, simple structure, and low cost.

[0029] like Figure 1 As shown, the system includes a near-end base station, a far-end FEM, a multi-mode optical fiber and a single-mode optical fiber. The near-end base station is used to process baseband signals, modulate the baseband signals to the optical wave frequency band, and generate energy signals; the multi-mode optical fiber is used to transmit energy signals between the near-end base station and the far-end FEM; the single-mode optical fiber is used to transmit radio frequency signals between the near-end base station and the far-end FEM; the far-end FEM is used to receive energy signals transmitted through the multi-mode optical fiber, convert the energy signals into electrical energy for power supply, and receive optical signals transmitted through the single-mode optical fiber, and demodulate them into radio frequency signals.

[0030] By adopting dual-fiber optical signal and energy simultaneous transmission technology, the signal and energy are transmitted through single-mode optical fiber and multi-mode optical fiber respectively, realizing the passive design of remote FEM without external power supply, simplifying the system layout, reducing installation and maintenance costs, and improving the signal isolation and transmission efficiency of the system. It is suitable for 5G network coverage with high information density and can provide stable and high-speed 5G communication services over long distances and large areas. Combining optical signal and energy simultaneous transmission, RoF technology, photonic-wireless fusion, 5G micro base stations, and passive distributed remote FEM systems, 5G signal coverage with long distance, large bandwidth, and ultra-high information density is achieved. The remote FEM does not require external power supply, the equipment is simple, and the site layout is simple.

[0031] The near-end base station includes a near-end RRU, an optical modulator, an optical demodulator, an attenuator and a circulator; the near-end RRU is connected to the first port of the circulator, the second port of the circulator is connected to the optical modulator through the attenuator, and the third port of the circulator is connected to the optical demodulator. The near-end RRU (Remote Radio Unit) is a terminal device in wireless communication technology, which is a device for receiving and transmitting wireless signals, and can transmit wireless signals to mobile terminals or other devices, thereby realizing wireless communication. Since the near-end RRU is in TDD mode, Tx and Rx share a radio frequency port, and the Tx and Rx signals are separated by the circulator. The attenuator is connected to the second port of the circulator. When the near-end RRU outputs a downlink signal, the attenuator is used to adjust the signal strength to prevent the optical modulator from being saturated due to an excessively strong input signal. During the debugging and optimization process of this system, by adjusting the attenuator, the signal strength on the signal path can be accurately controlled to ensure that the system performance is optimal and the system runs stably and efficiently. By using the attenuator reasonably, the system performance can be optimized, the service life of the equipment can be extended, and the signal transmission quality can be improved. The optical modulator is connected to the remote FEM via a first single-mode optical fiber, and the optical demodulator is connected to the remote FEM via a second single-mode optical fiber.

[0032] The remote FEM includes an optical demodulator, an optical modulator, a first remote power amplifier, a second remote power amplifier, a first low noise amplifier, a second low noise amplifier, a filter and a photovoltaic power supply; the optical demodulator is connected in sequence to the second remote power amplifier, i.e., remote PA2, the first remote amplifier, i.e., remote PA1, a transmitting filter, i.e., a Tx filter, and a transmitting antenna; the optical modulator is connected in sequence to the first low noise amplifier, i.e., remote LNA1, the second low noise amplifier, i.e., remote LNA2, a receiving filter, and a receiving antenna.

[0033] The optical demodulator or optical modulator of the near-end base station and the far-end FEM respectively adopts a RoF demodulator or RoF modulator with temperature compensation function. Temperature compensation can make the RoF demodulator and RoF modulator always work at the best working point, improve energy efficiency and overall system performance, reduce unnecessary energy loss, and improve energy utilization.

[0034] By real-time monitoring and adjusting working parameters, the stability of equipment performance can be maintained under different temperature conditions, signal quality can be improved, system reliability can be enhanced, equipment life can be extended, and maintenance costs can be reduced, thereby ensuring that the RoF-based passive distributed 5G micro base station system can provide high-quality communication services under various environmental conditions.

[0035] The single-mode optical fiber includes a first single-mode optical fiber and a second single-mode optical fiber; the optical modulator of the near-end base station is connected to the optical demodulator of the remote FEM through the first single-mode optical fiber; the optical modulator of the remote FEM is connected to the optical demodulator of the near-end base station through the second single-mode optical fiber. Transmitting downlink signals through the first single-mode optical fiber and uplink signals through the second single-mode optical fiber can completely avoid mutual interference between uplink and downlink signals, and improve signal quality and stability. A separate optical fiber path can effectively reduce echo and reflection problems, improve the integrity of signal transmission, and reduce echo and reflection.

[0036] The first single-mode optical fiber and the second single-mode optical fiber can carry uplink and downlink data transmission respectively, making the bandwidth utilization of each optical fiber more efficient. Independent optical fiber transmission can reduce signal loss, improve transmission distance and signal quality, achieve higher data transmission rate, meet the large-capacity and high-speed 5G communication requirements, and improve bandwidth and capacity. The use of two single-mode optical fibers can simplify the design of optical modulators and optical demodulators, reduce complexity, and reduce the difficulty of design and implementation. Independent uplink and downlink transmission paths make system debugging and troubleshooting more convenient, and can quickly locate and solve problems, which is convenient for system debugging and maintenance. When a certain optical fiber fails, it will not affect the transmission of another optical fiber, improving the overall robustness and reliability of the system. According to different application requirements, the bandwidth and transmission distance of the uplink and downlink optical fibers can be flexibly configured to meet the communication requirements of different scenarios, facilitate future system expansion and upgrades, and increase or adjust the number of optical fibers and transmission parameters according to demand, with strong scalability.

[0037] The near-end base station is also provided with a light emitter, which generates energy laser through the light emitter, and the energy laser is transmitted to the remote FEM through a multimode optical fiber. The light emitter converts it into an optical signal through an internal light source, such as a laser diode, so as to be transmitted in the optical fiber. The selection of the light emitter requires that the effective transmission power is greater than the power consumption requirement of the remote radio frequency unit, where the effective transmission power Pl = the output power Po of the light emitter * the photoelectric transmission conversion efficiency. The optical signal is transmitted through a multimode optical fiber, that is, the modulated optical signal is sent to the remote device through the optical fiber to achieve high-speed and long-distance data transmission. In the optical signal energy simultaneous transmission system, the light emitter is used to generate a high-power laser, and transmits light energy to the remote FEM through a multimode optical fiber. The remote device converts the light energy into electrical energy through a photovoltaic cell for its own use. The light emitter can support the transmission of high-frequency signals, adapt to the large bandwidth requirements of the 5G network, ensure the efficient operation and coverage performance of the system, and the remote FEM does not require external power supply, and can achieve long-distance, large bandwidth, and ultra-high information density 5G signal coverage, with simple equipment and simple station layout.

[0038] Use multimode optical fiber to transmit energy. Multimode optical fiber has a larger core diameter and higher power transmission capacity. It can transmit high-power lasers to meet the power supply requirements of remote FEMs and equipment. The high-power optical signal transmitted by multimode optical fiber is converted into electrical energy by photovoltaic cells or photoelectric conversion devices at the remote end, providing a stable power supply for remote equipment. It can realize centralized power supply at the remote end, avoid the need for external power supply for remote equipment, simplify installation and maintenance, and can efficiently convert the transmitted optical energy into electrical energy to reduce energy loss. By using a single multimode optical fiber to transmit energy, the optical fiber wiring design in the system is simplified, reducing wiring complexity and cost. The energy transmission path is independent of the signal transmission path, avoiding the interference of high-power optical signals on data transmission signals, and improving the overall reliability and stability of the system. The optical power of the multimode optical fiber can be flexibly adjusted according to the power consumption requirements of the remote equipment to meet the power supply requirements of different equipment and application scenarios.

[0039] In uplink signal transmission, Figure 2 As shown, the remote FEM receives the uplink signal and modulates it to the optical frequency band to form an optical carrier signal, which is transmitted to the near-end base station through the second single-mode optical fiber. The Rx antenna receives the wireless signal from the user terminal UE and converts it into an RF signal. The remote filter filters out the out-of-band interference, amplifies it through the remote low-noise amplifier, enters the optical modulator, modulates the RF signal to the optical frequency band, and transmits it back to the near-end base station through the second single-mode optical fiber. The RF signal is restored by the optical demodulator at the near-end base station, and then passes through the circulator to the Rx channel of the near-end RRU.

[0040] In the downlink signal transmission, the near-end base station modulates to an optical carrier signal, transmits it to the remote FEM through the first single-mode optical fiber, and the remote FEM demodulates the optical carrier signal into an RF signal. The near-end RRU outputs the downlink signal, passes through the circulator and attenuator, and is given to the optical modulator, which modulates the RF signal to the optical frequency band, pulls it away through the first single-mode optical fiber, and restores the RF signal through the optical demodulator at the remote FEM, and then amplifies the RF signal through the remote power amplifier, filters out the out-of-band spurious, and outputs the wireless signal through the Tx antenna.

[0041] Furthermore, the present application can also be applied to FDD mode. Figure 3 As shown in the figure, in FDD mode, the receiving antenna is set separately from the transmitting antenna, and the near-end RRU is connected to a duplexer to separate the Tx and Rx RF signals. The far-end FEM uses a Tx filter to filter out-of-band spurious signals to avoid interfering with the Rx channel in the Rx frequency band. At the same time, the Rx filter is used to filter out out-of-band interference and large signal interference in the Tx frequency band, so that the Rx channel works in the linear region. The working principle of other parts is the same as that of the TDD mode.

[0042] More, in FDD mode, such as Figure 4As shown in the figure, the receiving antenna and the transmitting antenna are in a co-antenna mode, and the near-end RRU is connected to a duplexer to separate the Tx and Rx RF signals. The remote FEM uses a duplexer to combine Tx and Rx into the same antenna, and the Tx channel filters out-of-band spurious signals to avoid interference with the Rx channel in the Rx frequency band; at the same time, the Rx channel filters out-of-band interference and large signal interference in the Tx frequency band, so that the Rx channel works in the linear region. The working principle of other parts is the same as that of the TDD mode.

[0043] The TDD mode frequencies of 5G NR (5G New Radio, a global 5G standard based on a new air interface design of OFDM) are 2515-2675MHz, 3300-3400MHz, 3400-3600MHz, 4800-5000MHz (BW=100MHz / 160MHz), and the FDD mode frequency band is 703~803MHz (uplink 703~748MHz, downlink 758~803MHz, BW=30MHz / 45MHz). The corresponding architecture can be selected for different frequency bands. Since the bandwidth of the TDD mode is large, the rate of this mode is large and the information density is high. The frequency band of the FDD mode is low and the path loss is small, so the wireless coverage range of this mode is large. In practical applications, the mode to be adopted can be determined according to the specific communication requirements, and this application does not limit it.

[0044] Conduct a downlink peak rate test on this system. Figure 1 This is the connection mode of a transceiver channel in this system. In the verification experiment, four transceiver channels were built, namely one near-end RRU plus a 4-channel far-end FEM, to achieve 4-transmit 4-receive full-duplex communication, with an operating frequency of 4800MHz to 5000MHz, a signal bandwidth of 100MHz, a peak rate greater than 1000Mbps, and EVM<2.8%.

[0045] Figure 2 This is the networking diagram for the downlink peak rate test. After UE1 accesses this system, it goes through the following links: server->switch->BBU->RRU->remote FEM->wireless side->UE1 to implement the downlink peak rate packet filling service.

[0046] The near-end RRU outputs the downlink signal, which is given to the optical modulator through the circulator and attenuator. The RF signal is modulated to the optical frequency band, pulled away through the first single-mode optical fiber, and the RF signal is restored by the optical demodulator at the far-end FEM. The RF signal is amplified by the far-end PA, and the out-of-band spurious signals are filtered out by the filter, and the wireless signal is output through the Tx antenna.

[0047] During the uplink signal transmission process, the Rx antenna receives the wireless signal of the UE, converts it into an RF signal, and filters out out-of-band interference. The signal is amplified by the remote LNA and given to the optical modulator, which modulates the RF signal to the optical frequency band. The signal is then transmitted back to the near end through the single-mode optical fiber 2. The RF signal is restored by the optical demodulator at the near end, and then passed through the circulator to the Rx channel of the RRU.

[0048]

[0049] The downlink peak rate test results are as follows:

[0050] 10.00-11.00sec 115MBytes 966MBlts / sec

[0051] 11.00-12.00sec 124MBytes 1.04Gblts / sec

[0052] 12.00-13.00sec 122MBytes 1.02Gblts / sec

[0053] 13.00-14.00sec 119MBytes 998MBlts / sec

[0054] 14.00-15.00sec 117MBytes 983MBlts / sec

[0055] 15.00-16.00sec 112MBytes 942MBlts / sec

[0056] 16.00-17.00sec 107MBytes 896MBlts / sec

[0057] 17.00-18.00sec 131MBytes 1.10Gblts / sec

[0058] 18.00-19.00sec 97.4MBytes 817MBlts / sec

[0059] 19.00-20.00sec 123MBytes 1.01Gblts / sec

[0060] 20.00-21.00sec 97.1MBytes 832MBlts / sec

[0061] 21.00-22.00sec 126MBytes 1.06Gblts / sec

[0062] 22.00-23.00sec 137MBytes 1.15Gblts / sec

[0063] 23.00-24.00sec 124MBytes 1.04Gblts / sec

[0064] 24.00-25.00sec 123MBytes 1.03Gblts / sec

[0065] 25.00-26.00sec 134MBytes 1.12Gblts / sec

[0066] 26.00-27.00sec 127MBytes 1.06Gblts / sec

[0067] 27.00-28.00sec 116MBytes 973MBlts / sec

[0068] 28.00-29.00sec 126MBytes 1.06Gblts / sec

[0069] 29.00-30.00sec 112MBytes 934MBlts / sec

[0070] 30.00-31.00sec 105MBytes 882MBlts / sec

[0071] 31.00-32.00sec 137MBytes 1.15Gblts / sec

[0072] 32.00-33.00sec 137MBytes 1.15Gblts / sec

[0073] 33.00-34.00sec 139MBytes 1.17Gblts / sec

[0074] 34.00-35.00sec 116MBytes 970MBlts / sec

[0075] 35.00-36.00sec 108MBytes 874MBlts / sec

[0076] 36.00-37.00sec 106MBytes 920MBlts / sec

[0077] From the above test results, it can be seen that the peak rate reaches 1Gbps.

[0078] In the downlink power test, it can be seen that Figure 5 As shown in Figure 1, the transmission power is not less than 24dBm, i.e. 250mW. Figure 6 As shown in the figure, the downlink EVM test result is EVM<2.8%.

[0079] The relationship between EVM and input energy optical power is shown in the following table. It can be seen that EVM has nothing to do with changes in input energy optical power.

[0080] Table 1 Relationship between EVM and input energy optical power

[0081]

[0082] The test results of 1km optical fiber energy transmission efficiency are as follows. It can be seen that the 1km optical fiber energy transmission efficiency is >10.3%.

[0083] The 1km optical fiber energy transmission efficiency test is shown in Table 2:

[0084] Table 2 1km optical fiber energy transmission efficiency test table

[0085]

[0086]

[0087] This application adopts dual-fiber optical signal and energy simultaneous transmission technology to transmit the uplink and downlink signals respectively through single-mode optical fibers, and efficiently transmits energy through a single multi-mode optical fiber, thereby realizing a passive design of the remote FEM without the need for external power supply, simplifying the system layout, reducing installation and maintenance costs, and improving signal isolation and transmission efficiency. It is suitable for high-information-density 5G network coverage and can provide stable and high-speed 5G communication services over long distances and a large range.

[0088] The processing method of the system can refer to the description of the above method and will not be repeated here.

[0089] The present invention also provides a device, which may include: a memory storing executable program code;

[0090] a processor coupled to the memory;

[0091] A transceiver used to communicate with other devices or communication networks and to receive or send network messages;

[0092] A bus used to connect memory, processors, and transceivers for internal communication.

[0093] The transceiver receives messages transmitted over the network and passes them to the processor via the bus. The processor calls the executable program code stored in the memory through the bus for processing, and passes the processing results to the transceiver via the bus for transmission, thereby realizing the system provided in the embodiment of the present application.

[0094] An embodiment of the present application also provides a non-transitory machine-readable storage medium, on which an executable program is stored. When the executable program is executed by a processor, the processor executes the system provided in the above embodiment.

[0095] An embodiment of the present invention discloses a computer-readable storage medium storing a computer program for electronic data exchange, wherein the computer program enables a computer to execute the described system.

[0096] An embodiment of the present invention discloses a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to enable a computer to execute the described system.

[0097] The embodiments described above are only illustrative, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, i.e., they may be located in one place, or they may be distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without paying creative labor.

[0098] Through the specific description of the above embodiments, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the above technical solution can be essentially or partly contributed to the prior art in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, and the storage medium includes a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0099] Finally, it should be noted that the embodiments disclosed in the present invention are only preferred embodiments of the present invention, which are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A passive distributed 5G micro base station system based on RoF, characterized in that: include: The near-end base station is used to process the baseband signal and modulate the baseband signal to the optical wave frequency band; and generating energy signals; Multimode optical fiber, used to transmit energy signals between the near-end base station and the far-end FEM; Single-mode optical fiber, used to transmit radio frequency signals between the near-end base station and the far-end FEM; The remote FEM is used to receive the energy signal transmitted through the multimode optical fiber and convert the energy signal into electrical energy for power supply; Receives optical signals transmitted through single-mode optical fiber and demodulates them into RF signals.

2. According to claim 1, a passive distributed 5G micro base station system based on RoF is characterized in that: The remote FEM includes an optical demodulator, an optical modulator, a first remote power amplifier, a second remote power amplifier, a second low noise amplifier, a first low noise amplifier, a filter and a photovoltaic power supply; the optical demodulator is connected to the first remote power amplifier, the second remote amplifier, the filter and the transmitting antenna in sequence; the optical modulator is connected to the second low noise amplifier, the first low noise amplifier, the filter and the receiving antenna in sequence.

3. According to claim 2, a passive distributed 5G micro base station system based on RoF is characterized in that: The proximal base station includes a proximal RRU, an optical modulator, an optical demodulator, an attenuator and a circulator; the proximal RRU is connected to the first port of the circulator, the second port of the circulator is connected to the optical modulator through the attenuator, and the third port of the circulator is connected to the optical demodulator.

4. According to claim 3, a passive distributed 5G micro base station system based on RoF is characterized in that: The single-mode optical fiber includes a first single-mode optical fiber and a second single-mode optical fiber; the optical modulator of the near-end base station is connected to the optical demodulator of the far-end FEM through the first single-mode optical fiber; the optical modulator of the far-end FEM is connected to the optical demodulator of the near-end base station through the second single-mode optical fiber.

5. According to claim 4, a passive distributed 5G micro base station system based on RoF is characterized in that: In the uplink signal transmission, the far-end FEM receives the uplink signal and modulates it to the optical wave frequency band to form an optical carrier signal, and the optical carrier signal is transmitted to the near-end base station through the first single-mode optical fiber.

6. According to claim 4, a passive distributed 5G micro base station system based on RoF is characterized in that: In downlink signal transmission, the near-end base station receives the downlink signal and modulates it to the optical wave frequency band to form an optical carrier signal, which is transmitted to the far-end FEM through the second single-mode optical fiber. The far-end FEM demodulates the optical carrier signal into a radio frequency signal.

7. A RoF-based passive distributed 5G micro base station system according to claim 6, characterized in that: The near-end base station is also provided with a light emitter, which generates energy laser, and the energy laser is transmitted to the far-end FEM via a multi-mode optical fiber.

8. According to claim 4, a passive distributed 5G micro base station system based on RoF is characterized in that: The optical demodulator or optical modulator respectively adopts a RoF demodulator or RoF modulator with a temperature compensation function.

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