CN101272391A - Software Radio System Based on Ethernet Switching - Google Patents

Abstract

The software radio system based on Ethernet switching involves the field of wireless communication, and is characterized in that: general hardware (for example: commercial server, common PC and embedded system) is used as the platform of signal processing software, and this platform is the main platform, supplemented by other Various hardware unit modules are used to realize a specific communication system and complete corresponding signal processing functions. The core software processing platform based on general hardware is interconnected with other various hardware unit modules using standard Ethernet, and the exchange of data and control information between each other is realized through Ethernet exchange. Based on this, through the loading of special signal processing software and control software, supplemented by corresponding hardware modules to complete some specific functions, wireless communication devices with various functions can be realized. The system realized in this way has strong flexibility and reconfigurability, and greatly simplifies the system design.

Description

Software Radio System Based on Ethernet Switching

technical field

The invention relates to a software radio system based on Ethernet switching and its architecture.

Background technique

Software Defined Radio (SDR, Software Defined Radio) is a new technology and system proposed in recent years to realize wireless communication. It is based on modern communication theory, takes digital signal processing as the core, and supports microelectronics technology. It connects hardware unit modules in a standard and open form to form a general hardware platform. Functional open wireless communication equipment, so that the development of new wireless communication systems and new products will be gradually transferred to software.

The software radio system is mainly composed of antenna, radio frequency front end, digital front end, signal processing unit and various software. Among them, the RF front-end is responsible for completing the sending and receiving of analog signals; the digital front-end (including A/D-D/A and corresponding hardware processing units) completes digital signal filtering, interpolation/extraction, up/down conversion, etc., and communicates with signals through specific interfaces The processing unit completes the interaction of digital signals; the signal processing unit is mainly composed of a specific hardware platform, and its specific functions are realized by writing corresponding software programs.

Software radio is a brand new architecture, its main features are as follows:

(1) System hardware modularization

Modularization is to decompose the various tasks that define the system into mutually independent software and hardware modules, and these modules are logically connected through corresponding interfaces to form the required system functions. A modular system can dynamically change functions by adding or replacing modules without conflicting with other modules in the system. Well-defined interfaces between modules help enhance the design of modular systems.

(2) Reconfigurability

The most fundamental feature of software radio is reconfigurability, which is the ability of system functions to change with demand, also known as programmability. Software radio must support system reconfiguration in both software and hardware, so that it has the ability to define system functions by changing the running software. Having reconfigurability is a necessary condition for software radio, and software radio has system-level reconfiguration capability.

(3) Flexibility

The working mode can be changed by software programming, including programmable radio frequency band broadband signal access mode and programmable modulation mode, etc. Therefore, the channel access mode can be changed arbitrarily, the modulation mode can be changed or the signals of different systems can be received; the business can be expanded, the wireless communication environment can be analyzed, the enhanced business and real-time environment testing can be defined through software tools, the upgrade is convenient, and the equipment cost is reduced Expenses, thus greatly reducing the cost of the entire network.

Traditional software defined radios fall into two categories:

(1) Integrate multiple devices of different standards, such as the GSM-CDMA dual-mode mobile phones currently on the market. Obviously, this method can only be switched under several preset standards, and adding support for new standards means integrating more circuits, and the reconfiguration capability is very limited.

(2) Based on Field Programmable Gate Array (FPGA) and Digital Signal Processor (DSP), this type of programmable hardware has a greatly improved reconfiguration capability. However, languages such as VHDL and Verilog used for FPGA and assembly language of DSP are all products for specific manufacturers, which makes the software in this way depend too much on the specific hardware, and the portability is poor. In addition, for the majority of technicians, the threshold for FPGA and DSP development is still high, and the development process is relatively cumbersome.

Contents of the invention

In order to solve the problems existing in the traditional software radio system and construct a software radio system that is more general, more flexible, and easy to develop and apply, the present invention proposes a software radio system based on Ethernet switching.

The present invention is characterized in that:

A platform based on signal processing software including commercial servers, or PCs, or embedded systems, which has a unique MAC address;

A hardware unit with a setting function, which has a unique MAC address;

Ethernet is used for communication between the signal processing software platform and the hardware unit, and the exchange of data and control information between them is realized through the Ethernet exchange by using MAC packets conforming to IEEE802.3.

The system realized in this way has strong flexibility and reconfigurability. The well-defined standard interface between modules helps to enhance the design of the modular system and greatly simplifies the design and verification of the hardware part. In addition, , the core processing software can be developed using a high-level language, which has strong scalability and portability.

Description of drawings

Fig. 1 represents the architectural block diagram of the software radio system based on Ethernet switching of the present invention

Fig. 2 shows a structural block diagram of the system application example of the present invention.

Detailed ways

In terms of system architecture, the software radio system proposed in the present invention adopts general hardware (for example: commercial server, common PC and embedded system) as the platform of signal processing software, and has the following advantages: pure software Signal processing has great flexibility; general-purpose high-level language (such as C/C++) can be used for software development, with strong scalability and portability, and short development cycle; the general-purpose hardware-based platform has low cost and enjoys The various advantages brought about by the progress of computer technology (such as: the continuous improvement of CPU processing power and the progress of software technology, etc.).

With the above-mentioned signal processing software platform as the core, the key processing work of the system is completed by standard CPU, which can greatly reduce the complexity of system implementation, facilitate system maintenance and upgrade, and the processing capacity of the system will also increase with the improvement of CPU computing power. However, from the perspective of implementation, there are many functions that are not suitable to be implemented by pure software, such as signal filtering, channel decoding, etc., which requires a reasonable division of the processing work of each part of the system between software and hardware. It is suitable for processing algorithms that are completely implemented in software, and are accelerated by corresponding dedicated hardware processing units, so that software processing based on general-purpose hardware (such as: commercial servers, ordinary PCs, and embedded systems) platforms is the main form, and other various completion specific The functional hardware unit module is supplemented by the system architecture to realize the specific communication system and complete the corresponding signal processing functions. Wireless communication devices with various functions can be realized by loading special signal processing software and control software, supplemented by corresponding hardware modules to complete certain specific functions.

Between the core software processing platform based on general-purpose hardware (such as commercial servers, ordinary PCs, and embedded systems) and various other hardware unit modules that perform specific functions, well-defined interfaces are required to realize the interaction of data and control information. This is more conducive to realizing the modularization of specific functions, enhancing the design of the modular system, and ensuring the flexibility and good reconfigurability of the system.

In the present invention, standard Ethernet is used to realize interconnection between the core software processing platform based on general-purpose hardware (for example: commercial server, common PC and embedded system) and other various hardware unit modules that complete specific functions, and the data between each other And the exchange of control information is realized through Ethernet exchange. Each module (including signal processing software platform and various auxiliary hardware unit modules) has a unique MAC address, and the exchange of data and control information between each other adopts MAC packets conforming to the IEEE 802.3 standard and is realized through Ethernet switching .

The present invention is described below with reference to the accompanying drawings.

Design and implement a software radio system based on Ethernet switching, which is mainly divided into the following steps:

(1) Combined with system requirements and corresponding algorithms, rationally divide software and hardware functions. Most of the signal processing work can be done by the core software processing platform based on general-purpose hardware (such as: commercial servers, ordinary PCs and embedded systems), and the control work between various modules of the system is also very suitable to be realized by software. However, some specific processing has the characteristics of clear function, definite algorithm flow, and large amount of calculation, which are very suitable for hardware implementation, such as digital signal filtering, interpolation/decimation, up/down conversion, and channel decoding.

(2) Design and implement hardware unit modules that complete specific functions. This type of module has the characteristics of clear function, definite algorithm flow, and large amount of calculation. It can be designed as a dedicated hardware unit module, and uses a standard Ethernet interface as the external data and control interface.

(3) Design and implement software programs that complete signal processing and system control. This type of software uses general-purpose hardware (such as: commercial servers, ordinary PCs, and embedded systems) as a platform, and uses standard Ethernet interfaces as external data and control interfaces. The signal processing using pure software has great flexibility, and can use common high-level languages (such as C/C++) for software development, with strong scalability and portability, and short development cycle. The platform based on general-purpose hardware has low cost and can enjoy various advantages brought about by the progress of computer technology (such as: the continuous improvement of CPU processing power and the progress of software technology, etc.).

(4) The interconnection between software processing platforms based on general hardware and hardware unit modules is realized through Ethernet switching. The exchange of all data and control information in the system is realized through Ethernet exchange.

The system constructed in the above-mentioned manner can realize wireless communication devices with various functions through the loading of special signal processing software and control software, supplemented by corresponding hardware modules for certain specific functions. The system has strong flexibility and good reconfigurability. The core processing software can be developed using high-level language, which has strong scalability and portability.

For example, the invention can be used in the "wireless mobile image transmission system". The central station of the system adopts the software radio architecture based on Ethernet switching, and its architecture is shown in Figure 2. The system includes two software processing platforms based on a common platform, and the processing of baseband signals is completed through corresponding software programs. Since the system adopts a multi-antenna structure, the system contains several (M) digital front-end modules, which are implemented by hardware and connected to the corresponding antennas to complete the extraction (interpolation) and filtering of receiving (sending) signals, and the corresponding baseband The signal is exchanged through Ethernet to realize the interaction with the software processing platform. In addition, this system also includes a decoder based on hardware to complete the channel decoding work that is not suitable for software. The decoder also completes the data exchange with the software processing platform through Ethernet switching.

Although the present invention has been described with reference to the accompanying drawings, it will be understood by those skilled in the art that the present invention may be modified in various forms and details without departing from the spirit and scope of the present invention as defined by the appended claims. change.

Claims (1)

1. A software radio system based on Ethernet switching, characterized in that: A platform based on signal processing software including commercial servers, or PCs, or embedded systems, which has a unique MAC address; A hardware unit with a setting function, which has a unique MAC address; Ethernet is used for communication between the signal processing software platform and the hardware unit, and the exchange of data and control information between them is realized through the Ethernet exchange by using MAC packets conforming to IEEE802.3.

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