KR20060058836A - Apparatus and method for sdr based modem platform - Google Patents

Abstract

The present invention relates to an SDR based modem platform device and method of operation. SDR-based modem platform device according to the present invention, a modem platform designed to have flexibility and versatility to implement a variety of communication modem, comprising: at least one DSP module for digital modem signal processing; A single FPGA module connected to respective peripheral elements to determine a data transmission path and supply a control signal; RF analog module for transmitting and receiving wireless data with the DSP module; An ADC module connected to the RF analog module to receive an analog signal; A DAC module connected to the RF analog module to transmit an analog signal; A host CPU module that controls the FPGA module and the DSP module or exchanges various data and is responsible for downloading a program to the DSP module; And an external interface module for exchanging data with the outside. According to the present invention, in the implementation of the digital communication system, when configuring the platform by the method proposed in the present invention, it is possible to easily configure a variety of modulation and demodulation standards in a short time by using only one common hardware platform, thereby reducing the development period In other words, the best performance test is performed.

SDR, Modem Platform, FPGA, DSP, ADC, DAC

Description

SDD based modem platform device and operation method {Apparatus and Method for SDR based Modem Platform}

1 is a view showing the configuration and arrangement of each module according to an embodiment of the present invention.

2 is a diagram illustrating a connection state between FPGAs and respective devices according to an exemplary embodiment of the present invention.

3A is a diagram illustrating a method of configuring a DSP module for transmitting data transmission according to an embodiment of the present invention.

3B is a diagram illustrating a method of configuring a DSP module for data transmission of a receiver according to an embodiment of the present invention.

The present invention relates to an apparatus and a method for operating a modem platform based on SDR, and more particularly, to a reconfigurable hardware platform considering flexibility and expandability in implementing a communication system modem of various standards.

According to the recent development direction of communication systems, complex and various modem technologies are being applied due to high speed and high quality data transmission requirements. This trend has caused various modulation and demodulation algorithms to exist within a single specification, and system developers have difficulty in developing and validating these various algorithms. Efforts to test and develop the system sooner are needed to preoccupy the market. In carrying out this process, developing and verifying multiple modem technologies using a single modem platform will minimize development costs and reduce development time.

The concept of Software Defined Radio (SDR) as a reconfigurable radio, which is being actively researched and developed as a new technology, may be the most suitable solution to satisfy the above requirements. These SDR-based platforms must satisfy flexibility and versatility, and serve as test-beds that enable the quick configuration and testing of the required specifications and various modulation and demodulation communication systems in an easy way. Can be done.

The SDR (Software Defined Radio), the next-generation open-type wireless signal processing technology, can operate operating parameters such as bandwidth, modulation method, and maximum output that affect frequency usage without increasing hardware in order to increase the efficiency of limited frequency resources. It is an alternative technique. SDR is a technology that enables global communication without interruption by downloading application software on an open architecture single hardware platform to flexibly cope with various wireless access environments. It is being considered as a solution for integration.

In the case of a platform for a conventional communication system, it was mostly implemented as an ASIC (Application Specific Integrated Circuit). In this case, the problem of remanufacturing a circuit every time to test and develop various modulation and demodulation modems is there was. This caused wasted hardware, and the development period went too far.

Another type of communication system platform is a digital signal processor (DSP) based software modem, which is a combination of DSP and field programmable gate array (FPGA), which is more flexible than an ASIC type platform. However, this also does not take into account the concept of SDR in design, which is somewhat lacking in terms of flexibility and is not suitable for testing and verifying various modem technologies. This type of platform consists of a large number of DSPs and FPGAs that are designed the most in terms of capacity in case the modem complexity increases, which can waste hardware when developing smaller capacity modems. .

In addition, if the data transmission path is not flexibly regulated, problems can arise that pass unnecessarily past DSPs and FPGAs where data is not used.

As a prior art for more flexible configuration of the data transmission path, Korean Patent Registration No. 324206 (Invention; High Performance Software Modem Platform Board, Registrant; Korea Electronics and Telecommunications Research Institute) uses a plurality of high performance DSP chips and FPGAs. It provides a board-type high speed and high performance software modem platform, which is connected to a plurality of FPGAs and DSPs, and allows a complex programmable demodulation modem (CPLD) and a microprocessor to configure their connection paths. Algorithm implementation is possible.

In addition, Korean Patent Registration No. 353453 (Invention; Test apparatus and method of modem using broadband code division multiple access, Registrant; Samsung Electronics) is applied to multiple modem chips and DSPs in which CPU constitutes one modem module. The hardware control of the user software is performed through the parallel port interface, and the user software displays the DSP and ASIC, the status and input commands of the FPGA, and the respective DSP and ASIC, By modifying the register module associated with the FPGA, the modem can be configured for the desired system, allowing real-time control and verification.

In addition, Korean Patent Application No. 704231 (Name of the Invention; Reprogrammable Digital Wireless Communication Device and Its Operation Method, Applicant; Mopix Technology INC) is a single device that can support various wireless communication standards and applications efficiently and at low cost. To provide a wireless communication device, which may be reprogrammed under the control of software that resides in, or is downloaded into, the memory and may be used by a microprocessor, digital signal processing processor, or heterogeneous multiprocessing logic circuit.

As such, the function to more flexibly configure the data transmission path has been presented in the paper including the existing patent, but since it is designed for a specific purpose, it is difficult to view the SDR concept due to the lack of generality. The disadvantages of wasting this limited, unused DSP or FPGA still remain a problem.

In order to solve the above problems, a modem platform composed of one or more DSPs and a single FPGA to support various modem algorithms, and each DSP should be modularized so that software can be downloaded from the CPU and be monitored in real time. do.

In addition, according to the complexity, capacity, and type of various modems, the configuration of the DSP module used for transmission and reception should be freely made, the transmission path setting of data passing through it should be flexible, and for the DSP module not used to reduce hardware waste. Consideration should also be made.

Accordingly, an object of the present invention is to provide an SDR-based modem platform device and a method of operation, which are flexible and appropriately reconfigurable to be able to verify various modem technologies.

As a means for achieving the above object, SDR-based modem platform device according to the present invention,

In a modem platform designed to be flexible and versatile to implement various communication modems,

One or more Digital Signal Processor (DSP) modules for digital modem signal processing;

A single field programmable gate array (FPGA) module connected to respective peripheral devices to determine a data transmission path and supply a control signal;

RF (Radio Frequency) analog module for transmitting and receiving wireless data with the DSP module;

An analog digital converter (ADC) module connected to the RF analog module to receive an analog signal;

A digital analog converter (DAC) module connected to the RF analog module to transmit an analog signal;

A host CPU module that controls the FPGA module and the DSP module or exchanges various data and is responsible for downloading a program to the DSP module; And

External interface module for data exchange with the outside

Characterized in that it comprises a.

In addition, as another means for achieving the above object, SDR-based modem platform operating method according to the present invention,

In a modem platform designed to be flexible and versatile to implement various communication modems,

a) the FPGA module receives data from the MII module;

b) processing the data into a digital modem signal at a DSP module; And

c) sending the processed data to the RF analog module via the DAC module

Characterized in that it comprises a.

In addition, as another means for achieving the above object, SDR-based modem platform operating method according to the present invention,

In a modem platform designed to be flexible and versatile to implement various communication modems,

a) the FPGA module receives data from the ADC module;

b) the FPGA module sending the data to a DSP module;

c) receiving data again after causing digital modem signal processing; And

d) delivering the received data back to the MII module and receiving it to a higher layer;

Characterized in that it comprises a.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the modem platform apparatus and operation method of the SDR concept according to an embodiment of the present invention.

First, in the present invention, the FPGA module sets a data transmission path so that each DSP module can be freely configured, the host CPU module can download a program to each corresponding DSP module, and the operating state of each DSP module in real time. It is composed of a structure that can monitor and control.

1 is a block diagram showing an SDR-based modem platform using a plurality of DSP modules and a single FPGA module according to an embodiment of the present invention.

Four DSP modules 13-16, which handle digital modem signal processing, are designed to be detachable in the form of daughter boards, and each includes a JTAG (Joint Test Action Group) interface port. Motion monitoring is possible.

 Each DSP module is connected to the FPGA module 17. The FPGA 17 module performs a free data transfer path setting function between the connected DSP modules 13 to 16, and is difficult to process with the DSP module. Impulse Response) It is also responsible for simple and high speed operations such as filtering.

Analog Digital Converter (ADC) 11 and Digital Analog Converter (DAC) devices are connected to a radio frequency (RF) analog module 19 having an independent configuration by a cable or a connector. And serves as an interface between the RF module 19.

The host CPU module 18 is connected to each of the DSP modules 13 to 16 to reconfigure the modem through program download to each DSP module, and to perform functions such as real time operation monitoring and data transmission. Perform.

2 is a block diagram illustrating a form in which the FPGA module 101 according to an embodiment of the present invention is connected to a plurality of DSP modules 102 to 105.

For the flexible configuration of each DSP module 102-105, which is one of the features of the present invention, the FPGA module is connected to each DSP module as shown in FIG.

There is basically one DSP module 102 for transmitting and one DSP module 103 for receiving to simplify and simplify the configuration of the modem. In the implementation of a complex modem algorithm, if it is impossible to process the single Tx DSP module 102 or the Rx DSP module 103, the DSP modules 104 and 105 may be further expanded. have. In this case, the FPGA module 101 establishes a data transmission path and connects the DSP modules 104 and 105 to be expanded.

Although only a total of four DSP modules are shown in FIG. 2, in consideration of more flexibility and scalability, the board may be configured by increasing additional expansion DSPs. Even so, the overall board configuration is the same, and the FPGA module 101 only needs to set the data transmission path.

In addition, since all DSP modules in the structure of the present invention are mounted on a board in the form of a daughter board, additional DSP modules that are not in use can be separated, thereby minimizing hardware loss. Each DSP module has a JTAG port, which can be externally verified and monitored in real time.

The FPGA module 101 is connected to the ADC module 107, the DAC module 108, the MII (Media Independent Interface) module 111, and the SDAC (DDS output DAC) module 109, respectively, to exchange data from the outside. have. Each of the dedicated DSP module 102 and the receiving DSP module 103 is connected with one first in first out (FIFO) element, which serves as a data buffer for transmitting and receiving, respectively. 105, only one FIFO exists. This is because the additional expansion DSP module 104, 105 is directly connected to the FIFO element for buffering data from the dedicated transmit / receive DSP module 102, 103.

3A illustrates a method of configuring a transmitting end according to an embodiment of the present invention. That is, one to three DSP modules can be configured according to the complexity of the transmitter. In this case, the data transmission path setting methods 201, 202, and 203 of the FPGA module are shown.

The FPGA module 204 processes the data received from the MII module 206 as a digital modem signal in the DSP module and then exports the data to the RF analog module through the DAC module 205. In this process, the DSP module can be configured in three ways.

Firstly, when only the transmission (Tx) DSP module 207 is used (201), and second, when the transmission (Tx) DSP module 207 and an additional one DSP module 208 are further used ( 202 and, thirdly, a transmission (Tx) DSP module 207 and two DSP modules 208 and 209.

3b illustrates a method of configuring a receiving end according to an embodiment of the present invention. Like the transmitter described with reference to FIG. 3A, up to three DSP modules may be configured according to complexity. For each of these methods, the data transmission path setting methods 301, 302, and 303 of the FPGA module are shown.

The FPGA module 304 passes the data received from the ADC module 305 to the DSP module to process the digital modem signal, and then receives the data and delivers the data to the MII module 306 to pass it to the upper layer. In this process, the DSP module can be configured in three ways.

First, when only the receiving (Rx) DSP module 307 is used (301), and second, when the receiving (Rx) DSP module 307 and an additional one DSP module 308 are further used ( 302, and thirdly, a case where the receiving (Rx) DSP module 307 and two DSP modules 308 and 309 are further used.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made in the art without departing from the technical spirit of the present invention. It is obvious to one with ordinary knowledge.

The present invention relates to a modem platform based on a reconfigurable SDR technology that can implement various communication system modems, and can verify operation in real time, and when designing and verifying various demodulation algorithms for communication. Applying the present invention, one common platform can be used to achieve an optimal modem platform implementation in less time without wasting hardware.

In addition, the present invention can monitor the operating status of each part of the modem in real time, thereby reducing the development period, and has the effect of obtaining optimum performance.

Claims (25)

In a modem platform designed to be flexible and versatile to implement various communication modems, One or more Digital Signal Processor (DSP) modules for digital modem signal processing; A single field programmable gate array (FPGA) module connected to respective peripheral devices to determine a data transmission path and supply a control signal; RF (Radio Frequency) analog module for transmitting and receiving wireless data with the DSP module; An analog digital converter (ADC) module connected to the RF analog module to receive an analog signal; A digital analog converter (DAC) module connected to the RF analog module to transmit an analog signal; A host CPU module that controls the FPGA module and the DSP module or exchanges various data and is responsible for downloading a program to the DSP module; And External interface module for data exchange with the outside SDR-based modem platform device comprising a. The method of claim 1, SDR-based modem platform device including a first in first out (FIFO) for buffering high-speed data transfer between the DSP module and the FPGA module. The method of claim 1, An SDR-based modem platform device including a Joint Test Action Group (JTAG) interface unit connected between the FPGA module and the DSP module to exchange data. The method of claim 1, SDR-based modem platform device comprising a digital clock source device for supplying a clock (clock) of various speeds to the RF analog module, FPGA module, DSP module. The method of claim 1, The external interface module SDR-based modem platform device including an RS232 and Ethernet port. The method of claim 1, The DSP module is an SDR-based modem platform device, characterized in that designed to be removable in the form of a daughter board (Daughter) board. The method of claim 1, SFP-based modem platform device, characterized in that the FPGA module performs a simple and high-speed operation, such as finite impulse response (FIR) filtering difficult to process by the DSP module. The method of claim 1, The ADC module and the DAC module is an SDR-based modem platform device, characterized in that connected to the RF analog module having an independent configuration by a cable or connector. The method of claim 1, The host CPU module is connected to the DSP module is capable of reconfiguring the modem by downloading the program to the DSP module, SDR-based modem platform device, characterized in that to perform real-time operation monitoring and data transmission. The method of claim 1, The DSP module is a SDR-based modem platform device, characterized in that for simplifying the configuration of the modem divided into a transmission DSP module and a receiving DSP module. The method according to claim 1 or 10, SDR-based modem platform device further comprises a DSP module that can be further extended, if it is impossible to process by the transmitting and receiving DSP module. The method of claim 11, The further extended DSP module is SDR-based modem platform device, characterized in that the FPGA module to establish a data transmission path. The method of claim 11, SDR-based modem platform device, characterized in that configured to further expand the DSP module on the platform board. The method of claim 11, SDR-based modem platform device characterized in that the real-time verification and monitoring by configuring a JTAG port to each of the DSP. The method of claim 11, The further extended DSP module SDR-based modem platform device, characterized in that a single FIFO that acts as a data buffer for transmission and reception are connected. The method of claim 11, The DSP module is SDR-based modem platform device, characterized in that up to three depending on the complexity of the transmitter and the receiver. The method of claim 1, The FPGA module is an SDR-based modem platform device, characterized in that connected to the ADC module, DAC module, MII (Media Independent Interface) module, SDAC (DDS output DAC) module for transmitting and receiving data from the outside. In a modem platform designed to be flexible and versatile to implement various communication modems, a) the FPGA module receives data from a Media Independent Interface (MII) module; b) processing the data into a digital modem signal at a DSP module; And c) transmitting the processed data to an RF analog module via a DAC module SDR-based modem platform operating method comprising a. The method of claim 18, SDR-based modem platform operating method characterized in that for using the single transmission DSP module in the data transmission path configuration of the FPGA module. The method of claim 18, SDR-based modem platform operating method, characterized in that further using a single transmission DSP module and further extended DSP module in the data transmission path configuration of the FPGA module. The method of claim 18, SDR-based modem platform operating method characterized in that to use a single transmission DSP module and two further extended DSP module in the data transmission path configuration of the FPGA module. In a modem platform designed to be flexible and versatile to implement various communication modems, a) the FPGA module receives data from the ADC module; b) the FPGA module sending the data to a DSP module; c) receiving data again after causing digital modem signal processing; And d) delivering the received data back to the MII module and receiving it to a higher layer SDR-based modem platform operating method comprising a. The method of claim 22, SDR-based modem platform operating method characterized in that for using a single receiving DSP module in the data transmission path configuration of the FPGA module. The method of claim 22, SDR-based modem platform operating method further comprising using a single receiving DSP module and further extended DSP module in the data transmission path configuration of the FPGA module. The method of claim 22, SDR-based modem platform operating method characterized in that to use a single receiving DSP module and further extended two DSP module in the data transmission path configuration of the FPGA module.

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