TWM648760U - Digital circuit for multiple antenna remote radio head and radio unit - Google Patents

Abstract

A digital circuit consists of a plurality of digital circuits for the multiple antenna remote radio head (RRH) and radio unit (RU). For the digital circuit of the RRH, it has at least one programmable digital circuit or fixed digital circuit which includes a Common Public Radio Interface (CPRI). The other programmable digital circuit(s) and/or fixed digital circuit(s) include(s) one or more analog to digital converter (ADC) and digital to analog converter (DAC) module(s). For the digital circuit of the RU, it has at least one programmable digital circuit or fixed digital circuit which includes a fronthaul interface. The other programmable digital circuit(s) or fixed digital circuit(s) include(s) one or more signal processing module(s) of communications. The digital circuit can be used in the Massive MIMO base station such that the required transmit power can be reduced as a green technology.

Description

Digital circuits for multi-antenna long-distance radio frequency heads and radio frequency units

The new invention relates to a digital circuit inside a long-distance radio frequency head end and radio frequency unit in a wireless communication system.

In wireless communication applications such as wireless communication base station (Base Station) or satellite communication (Satellite Communications) ground station (Ground Station) system, there is a remote radio head (RRH) or radio unit (Radio Unit). RU) performs front-end Radio Frequency (RF) analog signal processing and digital signal processing, and performs its functions through RF Analog Circuit and Digital Circuit respectively. Since most current base stations or satellite communication ground stations use multiple antenna (Multiple Antenna) technology, the radio frequency analog circuit part in the long-range radio frequency head end or radio frequency unit will contain multiple radio frequency (RF) components and multiple radio frequency products. RF Integrated Circuit (RFIC) or integrated into a radio frequency integrated circuit, so that each antenna can correspond to a group of radio frequency analog circuit branches (RF Chain); while the existing technology uses a single radio frequency analog circuit in the digital circuit part. Single Chip architecture. For example: the digital circuit used for the long-range radio frequency headend disclosed in the World Intellectual Property Organization Patent Bulletin No. WO2015188145A1 announced on December 10, 2015 is a system on a chip (SOC) with a single-chip architecture, and An integrated circuit (IC) is used as an embodiment of the digital circuit.

Since the existing technology adopts a single-chip architecture in the digital circuit part, the digital circuit can be composed of programmable digital circuits, such as field programmable gate array (FPGA), system on chip (SOC), micro Controller (Micro-Controller, MCU), microprocessor (Micro-Processor Unit, MPU), digital signal processor (Digital Signal Processor, DSP), graphics processor (Graphics Processing Unit, GPU), central processing unit (Central Processing Unit (CPU), etc.; or fixed digital circuits, such as Application Specific Integrated Circuit (ASIC). However, if a single-chip digital circuit uses a programmable digital circuit, although it has the advantage of programmable modification and update, its circuit performance, such as power consumption and computing speed, is likely to be inferior to application-specific integrated circuits. On the contrary, if a single-chip digital circuit uses a fixed digital circuit, its circuit structure has been fixed and lacks the flexibility of future programmable modifications and updates. Especially in the application of base station systems, telecommunications companies usually require base stations to have a long service life, such as more than 10 years. Therefore, as international communication standards are updated, their digital circuits may need to be modified. Or update.

On the other hand, since the single-chip digital circuit has an integrated structure, if any part of the chip is damaged, it will easily cause the entire single-chip to fail to operate normally, causing the entire system to malfunction. And if repairs are needed, the entire single chip must be replaced, and only the internal damage cannot be replaced.

In addition, because single-chip digital circuits need to integrate all digital computing functions on one chip, the circuit structure is relatively complex, and the required R&D manpower and cost are also high. Usually only a few large chip design companies have the ability to do so. We provide single-chip digital circuit products, so the circuit costs tend to be higher.

Based on the above, existing single-chip digital circuits still have shortcomings such as lack of flexibility, short lifespan, low stability, difficult maintenance, and high cost, which still need to be improved.

In order to solve the above shortcomings of the prior art, the digital circuit of the present disclosure adopts a multi-chip architecture, which is composed of multi-chip digital circuits of programmable digital circuits and/or fixed digital circuits. By properly cutting the digital circuit functions required by the long-range radio frequency head end and radio frequency unit and allocating them to programmable digital circuits and/or fixed digital circuit chips, their multi-chip architecture can work together to achieve the desired results. Required functions.

One aspect of the present disclosure provides a digital circuit for a radio frequency unit, including one or a plurality of programmable digital circuits, and one or a plurality of fixed digital circuits, wherein at least one programmable digital circuit or fixed The digital circuit includes a fronthaul interface (Fronthaul Interface) module, and other programmable digital circuits and/or fixed digital circuits, including one or a plurality of communication signal processing modules; among which the programmable digital circuit and the fixed digital circuit can Placed on the same printed circuit board (PCB) or on different printed circuit boards. Each communication signal processing module includes Inverse Fast Fourier Transform (IFFT), Cyclic Prefix Addition (CP Addition), Crest Factor Reduction (CFR), and Digital Predistortion (Digital Prefix Addition). Pre-distortion (DPD), Digital Up Converter (DUC), Digital to Analog Converter (DAC), Analog to Digital Converter (ADC), Digital Down Converter (Digital Down Converter, DDC), remove cyclic prefix (Cyclic Prefix Removal, CP Removal), fast Fourier Transform (Fast Fourier Transform, FFT), physical random access channel (Physical Random Access Channel, PRACH) processing, Automatic Gain Control (AGC), In-phase and Quadrature (I/Q) signal compression (Compression) and decompression (Decompression), Antenna correction (Antenna) Calibration), and orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) phase compensation (Phase Compensation) at least one or a combination of more.

Another aspect of the present disclosure provides a digital circuit for a radio frequency unit, including a plurality of programmable digital circuits, where at least one programmable digital circuit includes a fronthaul interface module, and other programmable digital circuits include One or a plurality of communication signal processing modules; wherein a plurality of programmable digital circuits can be placed on the same printed circuit board or on different printed circuit boards. Each communication signal processing module includes inverse fast Fourier transform (IFFT), CP Addition, crest factor reduction (CFR), digital predistortion (DPD), digital upconverter (DUC), and digital analog conversion (DAC), analog-to-digital converter (ADC), digital downconverter (DDC), cyclic prefix removal (CP Removal), fast Fourier transform (FFT), physical random access channel processing, automatic gain control, At least one or a combination of at least one or more of in-phase and quadrature signal compression and decompression, antenna correction, and orthogonal frequency division multiplexing phase compensation.

Another aspect of the present disclosure provides a digital circuit for a radio frequency unit, including a plurality of fixed digital circuits, wherein at least one fixed digital circuit includes a fronthaul interface module, and the other fixed digital circuits include one or more A communication signal processing module; a plurality of fixed digital circuits can be placed on the same printed circuit board or on different printed circuit boards. Each communication signal processing module includes inverse fast Fourier transform (IFFT), CP Addition, crest factor reduction (CFR), digital predistortion (DPD), digital upconverter (DUC), and digital analog conversion converter (DAC), analog-to-digital converter (ADC), digital downconverter (DDC), remove Cyclic prefix (CP Removal), Fast Fourier Transform (FFT), physical random access channel processing, automatic gain control, compression and decompression of in-phase and quadrature signals, antenna correction, and orthogonal frequency division multiplexing phase compensation At least one or a combination of more of them.

Another aspect of the present disclosure provides a digital circuit for a long-range radio frequency headend, including one or a plurality of programmable digital circuits, and one or a plurality of fixed digital circuits, at least one of which is programmable. The circuit or fixed digital circuit includes a Common Public Radio Interface (CPRI) module, and other programmable digital circuits and/or fixed digital circuits include one or more analog-to-digital converters (ADCs) and digital Analog converter (DAC) module; the programmable digital circuit and the fixed digital circuit can be placed on the same printed circuit board or on different printed circuit boards.

According to the above, the long-range radio frequency headend and radio frequency unit digital circuits of the present disclosure have the flexibility of programmable modification and update, and have the better circuit performance of fixed digital circuits, such as low power consumption and faster computing speed. And because it adopts a multi-chip architecture, its stability and lifespan are easily better than that of a single-chip architecture. For example, in the application of radio frequency units with multi-antenna architectures, especially when the number of antennas is large, even if the digital circuit chips of some antenna branches appear When damaged, although the performance may be reduced, the entire system may still be able to operate normally and extend the service life. And when some chips are damaged, only the damaged chips need to be replaced instead of replacing all digital circuit chips, so it is easy to repair. Furthermore, since the circuit complexity of individual chips in a multi-chip architecture is relatively low, the threshold for technology development is low, and key technologies are not easily in the hands of a few large companies, which can potentially reduce overall circuit costs. In addition, the digital circuit disclosed in this disclosure is particularly suitable for use in wireless communication systems with a large number of antennas, such as large-scale multiple-input multiple-output antennas (Massive MIMO) base stations. Since large multiple-input multiple-output antenna base stations operate at the same data transfer rate Under certain conditions, as the number of antennas increases, the transmit power (Transmit Power) can be effectively reduced, and the reduced transmit power is proportional to the number of antennas. That is to say, the greater the number of antennas, the more the required transmit power can be reduced. Therefore, through appropriate design, the power consumption required by the base station can be reduced to achieve the green technology effect of energy saving and carbon reduction.

10: Wireless communication base station using long-range radio frequency headend

11a to 11c: Cable

12,102: Universal public radio frequency interface

100a to 100c: Antenna

110: Long-distance radio frequency headend

120,220,320: Support frame

130: Base frequency unit

20: Wireless communication base station using radio frequency unit

21a to 21c,31,42,52,63,72,82,91,1132: Prequel interface

200a to 200c, 300: RF unit

230,310: Distribution unit

30: Satellite communication ground station using radio frequency unit

40,103,1130a to 1130n: analog interface

41,50,51,60a to 60n,61a to 61n,62,70,71,80,81,90,101,1131a to 1131n: digital interface

400,500,600,700,800,900,1100: RF unit digital circuit

410,510,610,810,820,910,1010,1110: Programmable digital circuit

411,511,611,711,811,911,1111: Front pass interface module

420,520,620,630a to 630n,710,720,1020,1120a to 1120n: fixed digital electronics road

421,521,621,721,821,912: Beamforming and/or precoding module

422,522,631,722,822,920: Inverse Fast Fourier Transform (IFFT)

423,523,632,723,823,921: Add cycle prefix (CP Addition)

424: Crest Factor Reduction (CFR)

425: Digital predistortion (DPD)

426,1121:Digital upconverter (DUC)

427,1021,1122:Digital-to-analog converter (DAC)

428,524,633,724,824,922: Fast Fourier Transform (FFT)

429,525,634,725,825,923: Remove cycle prefix (CP Removal)

430,1123:Digital downconverter (DDC)

431,1022,1124:Analog-to-digital converter (ADC)

440a to 440n, 540a to 540n, 740a to 740n, 840a to 840n, 913a to 913n: communication signal processing module

1000: Long-distance radio frequency head-end digital circuit

1011: Common Common Radio Frequency Interface (CPRI) module

1030a to 1030n: Digital-to-analog converters and analog-to-digital converter modules

1112: Beam forming module

In order to make the present disclosure and embodiments more understandable, the accompanying drawings are described as follows:

[Figure 1] shows a schematic diagram of a base station with a long-range radio frequency head end.

[Figure 2] shows a schematic diagram of a base station with a radio frequency unit.

[Figure 3] shows a schematic diagram of a satellite communication ground station with a radio frequency unit.

[Fig. 4] is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure.

[Fig. 5] is a schematic diagram illustrating a digital circuit of a radio frequency unit according to another embodiment of the present disclosure.

[Fig. 6] is a schematic diagram of a digital circuit of a radio frequency unit according to another embodiment of the present disclosure.

[Fig. 7] is a schematic diagram of a digital circuit of a radio frequency unit according to another embodiment of the present disclosure.

[Fig. 8] is a schematic diagram of a digital circuit of a radio frequency unit according to another embodiment of the present disclosure.

[Fig. 9] is a schematic diagram of a digital circuit of a radio frequency unit according to another embodiment of the present disclosure.

[Fig. 10] is a schematic diagram of a long-range radio frequency head-end digital circuit according to an embodiment of the present disclosure.

[Fig. 11] is a schematic diagram of a digital circuit of a radio frequency unit used in a satellite communication ground station according to an embodiment of the present disclosure.

The following is a detailed description with examples and accompanying drawings, but the examples provided are not intended to limit the scope of this article. Any structure that is reassembled of components to produce a device with equal efficacy is within the scope of this article. In addition, the drawings are for illustrative purposes only and are not drawn to original size. To facilitate understanding, the same elements will be identified with the same symbols in the following description.

As used in this article, the definition of "programmable digital circuit" is: any digital circuit that can be modified or updated through programming language. For example: Field Programmable Gate Array (FPGA), System on Chip (SOC), Microcontroller (MCU), Microprocessor (MPU), Digital Signal Processor (DSP), Graphics Processing Unit, GPU), Central Processing Unit (Central Processing Unit, CPU), combinations of the above, and any other digital circuits that can be modified or updated with programming languages, are all within the scope of programmable digital circuits defined in this article.

As for the term "fixed digital circuit" used in this article, the scope of the definition is: any digital circuit that cannot be modified or updated through programming language. For example, application specific integrated circuits (ASICs) and any other digital circuits that cannot be modified or updated using programming languages are within the scope of fixed digital circuits defined in this article.

Regarding the "two-way transmission" used in this article, it means: if A transmits signals or data Two-way transmission of data to B means that A can send signals or data to B and/or B can send signals or data to A.

As used in this article, "Radio Unit (RU)" is a broad radio frequency unit, and its scope includes any system with antennas, radio frequency analog circuits, and digital circuits. For example, the Open Radio Unit (O-RU) specified by the Open Radio Access Network (O-RAN) organization is also within the scope of the radio frequency unit defined in this article. Other combinations include combined systems such as Open RF Unit (O-RU) plus Open Distributed Unit (O-DU), and satellite communication ground stations with antennas, RF analog circuits, and digital circuits. The system is also within the scope of the radio frequency unit defined in this article.

As used in this article, "Distributed Unit (DU)" is a generalized distributed unit, and its scope includes any device connected to the radio frequency unit through an interface and having a digital circuit, including related to the physical layer (Physical Layer, PHY). The system of calculation. For example, the Open Distributed Unit (O-DU) defined by the Open Radio Access Network (O-RAN) organization is also within the scope of the distributed unit defined in this article. Other combinations, such as combined systems such as open distributed units plus open central units (Open Central Unit, O-CU), and systems such as satellite communication ground stations that include physical layer related operations in the back end, are also defined in this article within the range of the distribution unit.

The "fronthaul interface" used in this article is a generalized fronthaul interface, and its scope includes any interface that can connect the radio frequency unit and the distribution unit. For example, the Fronthaul Interface specified by the Open Wireless Access Network Organization adopts the Enhanced Common Public Radio Interface (eCPRI) protocol and includes control Plane (Control Plane, C-Plane), user plane (User Plane, U-Plane), synchronization plane (Synchronization Plane, S-Plane), and management plane (Management Plane, M-Plane) are also defined in this article within the scope of the previously uploaded interface. The interface between the satellite communication ground station that connects the front-end radio frequency unit and the back-end distribution unit is also within the scope of the fronthaul interface defined in this article.

Please refer to Figure 1, which is a schematic diagram of a wireless communication base station using a long-range radio frequency headend. As shown in Figure 1, a wireless communication base station (Base Station) 10 includes antennas (Antenna) 100a to 100c, a long-range radio frequency head (RRH) 110, a support frame 120, a baseband unit (Baseband Unit, BBU) 130, and cables. (Cable) 11a to 11c, and Common Public Radio Frequency Interface (CPRI) 12.

The support frame 120 is mainly used for support, and the antennas 100a to 100c and the long-range radio frequency head 110 are installed on it. The antennas 100a to 100c are used to receive and transmit radio wave signals, and bidirectionally transmit analog high frequency signals to the long-range radio frequency head end 110 through the cables 11a to 11c. The long-range radio frequency headend 110 includes a radio frequency analog circuit and a digital circuit. The radio frequency analog circuit mainly performs analog signal processing including frequency up and down, filtering, and signal amplification and attenuation of radio frequency analog signals; while in the digital circuit This part is the core of this disclosure, mainly performing digital signal processing operations. Please refer to Figure 10 for an illustration of an embodiment of a long-range radio frequency head-end digital circuit. The long-range radio frequency head end 110 bidirectionally transmits digital data to the base frequency unit 130 through the common public radio frequency interface 12, where the base frequency unit 130 performs functions required by the base station including physical layer (PHY), media access control (Media Access Control) , MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (Radio Resource Control, RRC) and other functions.

Please refer to Figure 2. Figure 2 illustrates a wireless communication base station using a radio frequency unit. Schematic diagram. Different from the long-range radio frequency head end in Figure 1, the radio frequency units (RU) 200a to 200c integrate antennas, radio frequency analog circuits, and digital circuits, which can reduce or avoid cable losses in the long-distance radio frequency head end. And because the radio frequency unit and the antenna are highly integrated, it is more suitable for use in multi-antenna architectures with a large number of antennas, such as large multiple-input multiple-output antennas (Massive MIMO). Therefore, modern fifth-generation (5G) mobile communication base stations mostly use radio frequency The wireless communication base station of the unit. As shown in Figure 2, the wireless communication base station 20 includes radio frequency units (RU) 200a to 200c, a support frame 220, a distribution unit (DU) 230, and fronthaul interfaces 21a to 21c.

The support frame 220 is mainly used for support. Radio frequency units 200a to 200c are installed on it. Each radio frequency unit 200a to 200c includes an antenna, a radio frequency analog circuit, and a digital circuit. The antenna is used to receive and transmit radio wave signals. The radio frequency analog circuit mainly performs analog signal processing including frequency up and down, filtering, signal amplification and attenuation of the radio frequency analog signal. The digital circuit part is the core of this disclosure and is mainly used for For the operation of digital signal processing, please refer to the description of the digital circuit embodiment of the radio frequency unit in Figures 4 to 9. The radio frequency units 200a to 200c bidirectionally transmit digital data to the distribution unit 230 through the fronthaul interfaces 21a to 21c. The distribution unit 230 performs the requirements required by the base station including High Physical Layer (High-PHY), Media Access Control ( Media Access Control, MAC), and Radio Link Control (Radio Link Control, RLC) and other functions.

Please refer to Figure 3, which is a schematic diagram of a satellite communication ground station (Ground Station) using a radio frequency unit. As shown in FIG. 3 , the satellite communication ground station 30 includes a radio frequency unit (RU) 300 , a support frame 320 , a distribution unit (DU) 310 and a fronthaul interface 31 .

The support frame 320 is mainly used for support, and a radio frequency unit 300 is installed on it. The radio frequency unit 300 includes an antenna, a radio frequency analog circuit, and a digital circuit. antenna to receive To transmit radio wave signals, the radio frequency analog circuit mainly performs analog signal processing including frequency up and down, filtering, signal amplification and attenuation of the radio frequency analog signal, while the digital circuit part is the core of this disclosure and mainly performs digital signal processing. For calculation, please refer to Figure 11 which is an illustration of an embodiment of the digital circuit of the radio frequency unit of a satellite communication ground station. The radio frequency unit 300 bidirectionally transmits digital data to the distribution unit 310 through the fronthaul interface 31, where the distribution unit can perform physical layer (PHY) related operations required by the satellite communication ground station.

Please refer to FIG. 4 , which is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure. As shown in FIG. 4 , the radio frequency unit digital circuit 400 includes a programmable digital circuit 410 , a fixed digital circuit 420 , an analog interface 40 , a digital interface 41 , and a fronthaul interface 42 .

The programmable digital circuit 410 includes a fronthaul interface module 411, where the fronthaul interface module 411 is a transmitter and receiver of a fronthaul interface, capable of transmitting data from the radio frequency unit to the distribution unit through the fronthaul interface 42 and receiving the distribution unit through the fronthaul. The interface 42 transmits data to the radio frequency unit.

The fixed digital circuit 420 includes a beamforming and/or precoding module 421, and a plurality of communication signal processing modules 440a to 440n.

The beamforming and/or precoding module 421 includes two parts: beamforming and/or precoding. The beamforming is mainly used to perform beamforming operations on uplink (Uplink) and downlink (Downlink), and the precoding is used to Calculate the signal required to be transmitted by each downlink antenna.

Each communication signal processing module 440a to 440n includes two parts: transmission and reception. The transmission part includes Inverse Fast Fourier Transform (IFFT) 422 and Cyclic Prefix Addition (CP Addition). 423. Crest system Crest Factor Reduction (CFR) 424, Digital Pre-distortion (DPD) 425, Digital Up Converter (DUC) 426, and Digital to Analog Converter (DAC) 427. First, the frequency domain (Frequency Domain) signal will be converted into the time domain ( Time Domain) signal, and then limit the size of the signal within the set dynamic range through crest factor reduction 424, and then use digital predistortion 425 to compensate for the nonlinear distortion caused by the power amplifier (Power Amplifier) in the analog circuit. Finally, the signal sampling frequency and/or frequency shift is increased through the digital upconverter 426, and the digital signal is converted into an analog signal through the digital-to-analog converter 427, and then transmitted to the radio frequency analog circuit in the radio frequency unit.

Each communication signal processing module 440a to 440n includes an analog-to-digital converter (Analog to Digital Converter, ADC) 431, a digital downconverter (Digital Down Converter, DDC) 430, and a cyclic prefix remover in the receiving part. Prefix Removal, CP Removal) 429, and Fast Fourier Transform (Fourier Transform, FFT) 428. First, the analog signal of the radio frequency analog circuit will be converted into a digital signal through the analog-to-digital converter 431, and then through the digital downconverter 430 to reduce the signal sampling frequency and/or shift the frequency. Finally, by removing the cyclic prefix 429 and the fast Fourier Convert 428 to do the demodulation operation of orthogonal frequency division multiplexing and convert the time domain signal into a frequency domain signal.

The programmable digital circuit 410 and/or the fixed digital circuit 420 may also include the following modules: physical random access channel (PRACH) processing, automatic gain control (AGC), orthogonal frequency division multiplexing phase compensation (OFDM Phase) Compensation), antenna calibration (Antenna Calibration), and compression and decompression of in-phase and quadrature (I/Q) signals. Among them, physical random access The processing of incoming channels is mainly related to filtering of physical random access channels; automatic gain control is used to achieve the function of automatic gain adjustment; orthogonal frequency division multiplexing phase compensation provides compensation for orthogonal frequency division multiplexing Phase calculation; antenna correction, used to make the gain of the antenna and radio frequency circuit of the transmitting end and receiving end consistent; compression and decompression of in-phase and quadrature signals, used to reduce the data required to be transmitted and received by the fronthaul interface . To keep the diagram in Figure 4 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 4 .

As shown in Figure 4, data is transmitted bidirectionally between the programmable digital circuit 410 and the fixed digital circuit 420 through a digital interface 41. The digital interface 41 can use low-voltage differential signals such as JESD204 (A/B/C) and (Low-Voltage Differential Signaling, LVDS), PCIe (Peripheral Component Interconnect Express) and other interfaces or other interfaces; and the analog interface 40 is an analog signal interface, which can be used as an interface between the radio frequency analog circuit and the fixed digital circuit 420 bidirectional transmission interface.

Please refer to FIG. 5 , which is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure. As shown in FIG. 5 , the radio frequency unit digital circuit 500 includes a programmable digital circuit 510 , a fixed digital circuit 520 , a digital interface 50 , a digital interface 51 , and a fronthaul interface 52 .

The programmable digital circuit 510 includes a fronthaul interface module 511, where the fronthaul interface module 511 is a transmitter and receiver of a fronthaul interface, capable of transmitting data from the radio frequency unit to the distribution unit through the fronthaul interface 52 and receiving the distribution unit through the fronthaul. The interface 52 transmits data to the radio frequency unit.

The fixed digital circuit 520 includes a beam forming and/or precoding module 521 and a plurality of communication signal processing modules 540a to 540n.

Different from Figure 4, each communication signal processing module 540a to 540n in Figure 5 includes two parts: transmission and reception. The transmission part only includes the inverse fast Fourier transform (IFFT) 522 and the addition of cyclic prefix (CP Addition). )523, other digital circuits such as crest factor reduction, digital predistortion, digital upconverter, and digital-to-analog converter can be integrated into the RF analog circuit of the RF unit; while the receiving part only contains Fast Fourier Transform (FFT) 524, and removing the cyclic prefix (CP Removal) 525, other digital circuits such as analog-to-digital converters and digital downconverters can be integrated into the radio frequency analog circuit of the radio frequency unit.

The programmable digital circuit 510 and/or the fixed digital circuit 520 may also include the following modules: physical random access channel processing, automatic gain control, OFDM phase compensation, antenna correction, and in-phase and quadrature Signal compression and decompression. To keep the diagram in Figure 5 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 5 .

As shown in Figure 5, the programmable digital circuit 510 and the fixed digital circuit 520 bi-directionally transmit data through a digital interface 51, and the fixed digital circuit 520 can bi-directionally transmit data to the integrated radio frequency analog circuit through the digital interface 50. In the digital circuit, the digital interface 51 and the digital interface 50 can be implemented through interfaces such as JESD204 (A/B/C), low-voltage differential signaling, PCIe, or other interfaces.

Please refer to FIG. 6 , which is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure. As shown in Figure 6, the radio frequency unit digital circuit 600 includes a programmable digital circuit 610, a fixed digital circuit 620, fixed digital circuits 630a to 630n, digital interfaces 60a to 60n, digital interfaces 61a to 61n, a digital interface 62, and Prequel interface 63.

The programmable digital circuit 610 includes a fronthaul interface module 611, where the fronthaul interface module 611 is a transmitter and receiver of a fronthaul interface, capable of transmitting data from the radio frequency unit through the fronthaul. The interface 63 transmits data to the distribution unit and receives data transmitted from the distribution unit to the radio frequency unit through the fronthaul interface 63 .

Fixed digital circuit 620 includes beamforming and/or precoding modules 621.

Each fixed digital circuit 630a to 630n includes two parts: a transmitting part and a receiving part. The transmitting part includes an inverse fast Fourier transform (IFFT) 631 and a cyclic prefix (CP Addition) 632; and the receiving part includes a fast Fourier transform. (FFT) 633, and remove the cycle prefix (CP Removal) 634. Other digital circuits such as crest factor reduction, digital predistortion, digital upconverter, digital-to-analog converter, analog-to-digital converter, and digital downconverter can be integrated into the RF analog circuit of the RF unit.

The programmable digital circuit 610 and/or the fixed digital circuit 620 and/or the fixed digital circuits 630a to 630n may also include the following modules: physical random access channel processing, automatic gain control, orthogonal frequency division multiplexing phase Compensation, antenna correction, and compression and decompression of in-phase and quadrature signals. In order to keep the diagram in Figure 6 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 6 .

As shown in Figure 6, data is transmitted bidirectionally between the programmable digital circuit 610 and the fixed digital circuit 620 through a digital interface 62; between the fixed digital circuit 620 and the fixed digital circuits 630a to 630n through the digital interfaces 61a to 630n. 61n bidirectionally transmits data; and the fixed digital circuits 630a to 630n bidirectionally transmit data to digital circuits integrated in the radio frequency analog circuit through the digital interfaces 60a to 60n. The digital interface 62, the digital interfaces 61a to 61n, and the digital interfaces 60a to 60n can be implemented through interfaces such as JESD204 (A/B/C), low voltage differential signaling, PCIe, or other interfaces.

Please refer to FIG. 7 , which illustrates a radio frequency device according to an embodiment of the present disclosure. Schematic diagram of unit digital circuit. As shown in FIG. 7 , the radio frequency unit digital circuit 700 includes a fixed digital circuit 710 , a fixed digital circuit 720 , a digital interface 70 , a digital interface 71 , and a fronthaul interface 72 .

The fixed digital circuit 710 includes a fronthaul interface module 711, where the fronthaul interface module 711 is a transmitter and receiver of a fronthaul interface, capable of transmitting data from the radio frequency unit to the distribution unit through the fronthaul interface 72 and receiving the distribution unit through the fronthaul interface. 72The data sent to the radio frequency unit.

The fixed digital circuit 720 includes a beamforming and/or precoding module 721 and a plurality of communication signal processing modules 740a to 740n.

Each communication signal processing module 740a to 740n in Figure 7 includes two parts: transmitting and receiving. The transmitting part includes an inverse fast Fourier transform (IFFT) 722 and a cyclic prefix (CP Addition) 723; and the receiving part includes Parts include Fast Fourier Transform (FFT) 724 and Cyclic Prefix Removal (CP Removal) 725 . Other digital circuits such as crest factor reduction, digital predistortion, digital upconverter, digital-to-analog converter, analog-to-digital converter, and digital downconverter can be integrated into the RF analog circuit of the RF unit.

The fixed digital circuit 710 and/or the fixed digital circuit 720 may also include the following modules: physical random access channel processing, automatic gain control, orthogonal frequency division multiplexing phase compensation, antenna correction, and in-phase and quadrature signals Compression and decompression. In order to keep the diagram in Figure 7 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 7 .

As shown in Figure 7, the fixed digital circuit 710 and the fixed digital circuit 720 bi-directionally transmit data through a digital interface 71, and the fixed digital circuit 720 can bi-directionally transmit data through the digital interface 70 to be integrated into the radio frequency analog circuit. digital circuit, in which the digital interface 70 and The digital interface 71 can be implemented through interfaces such as JESD204 (A/B/C), low voltage differential signaling, PCIe, or other interfaces.

Please refer to FIG. 8 , which is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure. As shown in FIG. 8 , the radio frequency unit digital circuit 800 includes a programmable digital circuit 810 , a programmable digital circuit 820 , a digital interface 80 , a digital interface 81 , and a fronthaul interface 82 .

The programmable digital circuit 810 includes a fronthaul interface module 811, where the fronthaul interface module 811 is a transmitter and receiver of a fronthaul interface, capable of transmitting data from the radio frequency unit to the distribution unit through the fronthaul interface 82 and receiving the distribution unit through the fronthaul. The interface 82 transmits data to the radio frequency unit.

The programmable digital circuit 820 includes a beamforming and/or precoding module 821 and a plurality of communication signal processing modules 840a to 840n.

Each communication signal processing module 840a to 840n in Figure 8 includes two parts: transmitting and receiving. The transmitting part includes the inverse fast Fourier transform (IFFT) 822 and the CP Addition 823; and the receiving part includes Parts include Fast Fourier Transform (FFT) 824 and Cyclic Prefix Removal (CP Removal) 825 . Other digital circuits such as crest factor reduction, digital predistortion, digital upconverter, digital-to-analog converter, analog-to-digital converter, and digital downconverter can be integrated into the RF analog circuit of the RF unit.

The programmable digital circuit 810 and/or the programmable digital circuit 820 may also include the following modules: physical random access channel processing, automatic gain control, orthogonal frequency division multiplexing phase compensation, antenna correction, and in-phase and normal Compression and decompression of traffic signals. In order to keep the diagram of Figure 8 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 8 .

As shown in Figure 8, the programmable digital circuit 810 and the programmable digital circuit 820 transmit data bidirectionally through a digital interface 81, and the programmable digital circuit 820 can transmit data bidirectionally through the digital interface 80 to the radio frequency integrated circuit. For digital circuits in analog circuits, the digital interface 81 and the digital interface 80 can be implemented through interfaces such as JESD204 (A/B/C), low-voltage differential signals, PCIe, or other interfaces.

Please refer to FIG. 9 , which is a schematic diagram of a digital circuit of a radio frequency unit according to an embodiment of the present disclosure. As shown in FIG. 9 , the radio frequency unit digital circuit 900 includes a programmable digital circuit 910 , a digital interface 90 , and a fronthaul interface 91 . Although FIG. 9 only includes a programmable digital circuit 910, other digital circuits such as crest factor reduction, digital predistortion, digital upconverter, digital to analog converter, analog to digital converter, and digital downconverter modules It can be integrated into the radio frequency analog circuit chip of the radio frequency unit, so it also falls within the scope of the multi-chip digital circuit architecture of this disclosure. In order to keep the illustration in Figure 9 simple, the digital circuit integrated into the radio frequency analog circuit is not shown. enter.

The programmable digital circuit 910 includes a fronthaul interface module 911, a beamforming and/or precoding module 912, and a plurality of communication signal processing modules 913a to 913n.

The fronthaul interface module 911 is a transmitter and receiver of the fronthaul interface, capable of transmitting data from the radio frequency unit to the distribution unit through the fronthaul interface 91 and receiving data from the distribution unit to the radio frequency unit through the fronthaul interface 91 .

Each communication signal processing module 913a to 913n includes two parts: transmitting and receiving. The transmitting part includes the inverse fast Fourier transform (IFFT) 920 and the CP Addition 921; while the receiving part includes the fast Fourier transform (IFFT) 920 and the CP Addition 921. Fourier transform (FFT) 922, and cycle prefix removal (CP Removal) 923.

The programmable digital circuit 910 may also include modules for physical random access channel processing, automatic gain control, OFDM phase compensation, antenna correction, and compression and decompression of in-phase and quadrature signals. In order to keep the diagram in Figure 9 simple, these modules are not shown, but these modules can also be included in the digital circuit of Figure 9 .

The programmable digital circuit 910 bidirectionally transmits data to the digital circuit integrated in the radio frequency analog circuit through the digital interface 90 , where the digital interface 90 can pass through interfaces such as JESD204 (A/B/C), low voltage differential signaling, PCIe, or other interface to implement.

Please refer to FIG. 10 , which is a schematic diagram of a long-range radio frequency head-end digital circuit according to an embodiment of the present disclosure. As shown in Figure 10, the long-range radio frequency head-end digital circuit 1000 includes a programmable digital circuit 1010, a fixed digital circuit 1020, an analog interface 103, a digital interface 101, and a common common radio frequency interface (CPRI) 102.

The programmable digital circuit 1010 includes a common common radio frequency interface (CPRI) module 1011, where the common common radio frequency interface module 1011 is a transmitter and receiver of a common common radio frequency interface, capable of transmitting data from a long-distance radio frequency headend through a common The common radio frequency interface 102 transmits data to the base frequency unit and receives data transmitted from the base frequency unit to the remote radio frequency headend through the common public radio frequency interface 102 .

The fixed digital circuit 1020 includes digital-to-analog converters and analog-to-digital converter modules 1030a to 1030n, wherein each of the digital-to-analog converters and analog-to-digital converter modules 1030a to 1030n includes a digital-to-analog converter (DAC) 1021 and an analog-to-digital converter. Device (ADC)1022.

As shown in Figure 10, data is transmitted bidirectionally between the programmable digital circuit 1010 and the fixed digital circuit 1020 through a digital interface 101. The digital interface 101 can use low-voltage differential signals such as JESD204 (A/B/C) and , PCIe and other interfaces or other interfaces to achieve; while the class The analog interface 103 is an analog signal interface and can be used as a bidirectional transmission interface between the radio frequency analog circuit and the fixed digital circuit 1020 .

Please refer to FIG. 11. FIG. 11 is a schematic diagram illustrating a digital circuit of a radio frequency unit of a satellite communication system according to an embodiment of the present disclosure. The digital circuit of the radio frequency unit can be applied to, for example, a satellite communication ground station (Ground Station) and a satellite. Satellite communication repeater (Repeater) and other systems. As shown in Figure 11, the radio frequency unit digital circuit 1100 includes a programmable digital circuit 1110, fixed digital circuits 1120a to 1120n, analog interfaces 1130a to 1130n, digital interfaces 1131a to 1131n, and a fronthaul interface 1132.

The programmable digital circuit 1110 includes a fronthaul interface module 1111 and a beamforming module 1112. The fronthaul interface module 1111 is a transmitter and receiver of the fronthaul interface and can transmit the data of the radio frequency unit to the distribution unit through the fronthaul interface 1132. The distribution unit receives data transmitted to the radio frequency unit through the fronthaul interface 1132; the beamforming module 1112 mainly provides beamforming operations for transmission and reception.

Each fixed digital circuit 1120a to 1120n includes two parts: transmitting and receiving. The transmitting part includes a digital upconverter (DUC) 1121 and a digital-to-analog converter (DAC) 1122; while the receiving part includes a digital downconverter. converter (DDC) 1123, and an analog-to-digital converter (ADC) 1124. In addition, the fixed digital circuits 1120a to 1120n can also be integrated into radio frequency analog circuits, and this digital circuit architecture also falls within the scope of this disclosure.

As shown in Figure 11, data are transmitted bidirectionally between the programmable digital circuit 1110 and the fixed digital circuits 1120a to 1120n through digital interfaces 1131a to 1131n. The digital interfaces 1131a to 1131n can pass data such as JESD204 (A/B/C) , low-voltage differential signals, PCIe and other interfaces or other interfaces; and the analog interfaces 1130a to 1130n are analog signal interfaces and can be used as A bidirectional transmission interface between the radio frequency analog circuit and the fixed digital circuits 1120a to 1120n.

40: Analog interface

41:Digital interface

42: Prequel interface

400: Radio frequency unit digital circuit

410: Programmable digital circuits

411: Prequel interface module

420: Fixed digital circuit

421: Beamforming and/or precoding module

422: Inverse Fast Fourier Transform (IFFT)

423: Add cycle prefix (CP Addition)

424: Crest Factor Reduction (CFR)

425: Digital predistortion (DPD)

426: Digital upconverter (DUC)

427:Digital-to-analog converter (DAC)

428: Fast Fourier Transform (FFT)

429: Remove cycle prefix (CP Removal)

430: Digital downconverter (DDC)

431:Analog-to-digital converter (ADC)

440a to 440n: Communication signal processing module

Claims (10)

A digital circuit for a radio frequency unit, which has a plurality of digital circuits, wherein each digital circuit is a separate digital circuit chip, so that the overall digital circuit is a multi-chip structure; the plurality of digital circuits includes one or a plurality of programmable programs programmable digital circuits, and one or more fixed digital circuits, at least one of which is a programmable digital circuit or a fixed digital circuit including a fronthaul interface module, and the other programmable digital circuits and/or fixed digital circuits include a Or a plurality of communication signal processing modules; the programmable digital circuit and the fixed digital circuit can be placed on the same printed circuit board or on different printed circuit boards. The digital circuit as described in claim 1, wherein programmable digital circuits, fixed digital circuits, and programmable digital circuits can be connected to each other through one or more interfaces. , its interface can be implemented by JESD204 (A/B/C), low-voltage differential signal, PCIe and other interfaces or other interfaces. As for the digital circuit described in claim 1, the communication signal processing module includes at least one of the following or a combination of more: inverse fast Fourier transform (IFFT), adding cyclic prefix (CP Addition), crest factor reduction (CFR) ), digital predistortion (DPD), digital upconverter (DUC), digital to analog converter (DAC), analog to digital converter (ADC), digital downconverter (DDC), CP Removal , Fast Fourier Transform (FFT), Physical Random Access Channel (PRACH) processing, Automatic Gain Control (AGC), Orthogonal Frequency Division Multiplexing Phase Compensation (OFDM Phase Compensation), Antenna Calibration, and In-phase and Compression and decompression of quadrature (I/Q) signals. A digital circuit for a radio frequency unit, which has a plurality of digital circuits, wherein each digital circuit is a separate digital circuit chip, so that the overall digital circuit is a multi-chip structure; the plurality of digital circuits includes a plurality of programmable digits Circuits, in which at least one programmable digital circuit includes a fronthaul interface module, and other programmable digital circuits include one or a plurality of communication signal processing modules; wherein a plurality of programmable digital circuits can be placed on the same printed circuit board on or on a different piece of printed circuit board. The digital circuit as described in claim 4, wherein a plurality of programmable digital circuits can be connected to each other through one or more interfaces, and the interfaces can be JESD204 (A/B/C), low voltage differential signals, PCIe, etc. Or use other interfaces to implement it. As for the digital circuit described in claim 4, the communication signal processing module includes the following: One or more combinations: Inverse Fast Fourier Transform (IFFT), CP Addition, Crest Factor Reduction (CFR), Digital Predistortion (DPD), Digital Upconverter (DUC), Digital Processing of analog converter (DAC), analog-to-digital converter (ADC), digital downconverter (DDC), cyclic prefix removal (CP Removal), fast Fourier transform (FFT), and physical random access channel (PRACH) , Automatic Gain Control (AGC), Orthogonal Frequency Division Multiplexing Phase Compensation (OFDM Phase Compensation), Antenna Calibration, and Compression and Decompression of in-phase and quadrature (I/Q) signals ). A digital circuit for a radio frequency unit, which has a plurality of digital circuits, wherein each digital circuit is a separate digital circuit chip, so that the overall digital circuit is a multi-chip structure; the plurality of digital circuits includes a plurality of fixed digital circuits , wherein at least one fixed digital circuit includes a fronthaul interface module, and other fixed digital circuits include one or a plurality of communication signal processing modules; wherein the plurality of fixed digital circuits can be placed on the same printed circuit board or on different boards. on the printed circuit board. The digital circuit as described in claim 7, wherein a plurality of fixed digital circuits can be connected to each other through one or more interfaces, and the interfaces can be JESD204 (A/B/C), low voltage differential signals, PCIe and other interfaces or It is implemented by other interfaces. As for the digital circuit described in claim 7, the communication signal processing module includes at least one of the following or a combination of more: inverse fast Fourier transform (IFFT), adding cyclic prefix (CP Addition), crest factor reduction (CFR) ), digital predistortion (DPD), digital upconverter (DUC), digital to analog converter (DAC), analog to digital converter (ADC), digital downconverter (DDC), CP Removal , Fast Fourier Transform (FFT), Physical Random Access Channel (PRACH) processing, Automatic Gain Control (AGC), Orthogonal Frequency Division Multiplexing Phase Compensation (OFDM Phase Compensation), Antenna Calibration, and In-phase and Compression and decompression of quadrature (I/Q) signals. A digital circuit for a long-distance radio frequency headend, which has a plurality of digital circuits, wherein each digital circuit is a separate digital circuit chip, so that the overall digital circuit is a multi-chip structure; the plurality of digital circuits includes one or more programmable digital circuits, and one or more fixed digital circuits, wherein at least one programmable digital circuit or fixed digital circuit includes a common common radio frequency interface (CPRI) module, the other programmable digital circuits and/ or fixed The digital circuit includes one or a plurality of analog-to-digital converters and digital-to-analog converter modules; the programmable digital circuit and the fixed digital circuit can be placed on the same printed circuit board or on different printed circuit boards.

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