JP2002141823A - Software radio equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that it is necessary to guarantee that software radio equipment becomes legally suitable when the ratio equipment newly runs a program since it is difficult to guarantee that the software radio equipment comply with the Wireless Telegraphy Act., only with a program when frequency to switch a novel program increases in the software radio equipment. SOLUTION: This device is provided with a table for determining a parameter for fixing the characteristics of a function element provided in the software radio equipment on the basis of single or plural standard items, which are external input parameters.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a software defined radio.

[0002]

2. Description of the Related Art In recent years, with the improvement of the processing capability of a DSP,
A so-called software radio, which realizes a part of the function of the radio by software, has appeared. This type of wireless device 5 typically includes an analog unit 51 as shown in FIG.
And ADC (Analog to Digital Converter) · DA
It comprises a C (Digital to Analog Converter) section 52, a digital section 53, and a memory section 54.

The analog section 51 includes a plurality of hardware units corresponding to a plurality of communication systems, and is used by switching to a desired one of the plurality of communication systems depending on the situation. The memory unit 54 stores a plurality of programs corresponding to each of the plurality of communication schemes.
These programs are updated as needed by replacing the memory unit 54, writing from an external device not shown in the figure, or writing the data received from outside by the software radio through the antenna 50 by the digital unit 53. It is a good thing.

[0004] The digital section 53 has a DSP 531, downloads a necessary program from the memory section 54 in accordance with a desired communication system, and executes the program to execute a signal necessary for the desired communication system. Implement processing means. Such software radio 5
Has features such as being able to handle a plurality of communication methods with a small hardware scale by replacing programs, and being able to easily respond to bug fixes and new functions of individual methods.

[0005]

As software radios become popular as terminal devices and the like, and the frequency of replacement of new programs increases, it is assured only by programs that software radios comply with the Radio Law. It will be difficult to do. To this end, it is necessary to ensure that a software defined radio becomes a legally valid radio when a program is newly executed, especially a legally valid radio that does not leak power to adjacent channels. The challenge is to ensure that

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a software defined radio according to the present invention is based on one or more standard items which are external input parameters. It is characterized by having a table for determining parameters for determining the characteristics of the functional elements included in the software defined radio.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An outline of a software defined radio according to the present invention will be described with reference to FIG. In FIG. 1, the software radio 1 according to the present invention is different from the conventional software radio 5 shown in FIG. This table 141 contains data for determining parameters for determining the characteristics of the functional elements inside the software defined radio for one or more standard items of the radio station as defined by the Radio Law. .

In the following, it is assumed that the above standard items are information on a modulation method, a signal transmission speed, an occupied frequency bandwidth, and adjacent channel leakage power, and that the above functional elements are filters. However, the present invention is not limited to the above-described case, and can be easily applied to a case including a description for determining a parameter for determining a characteristic of another functional element for another standard item.

Tables 1 and 2 provide the above filter parameters in the software defined radio of the present invention.
41 shows a configuration example.

[0010]

[Table 1]

[0011]

[Table 2]

The above Table 1 determines the FIR filter inside the software defined radio based on information on the modulation method, signal transmission speed and adjacent channel leakage power including the filter characteristics specified by a program obtained from the outside. Includes descriptions for Table 1 shows the contents of the analog section 11 and the ADC / DAC constituting the software defined radio 1.
It is prepared in advance for each terminal device supplied by each manufacturer based on the hardware specifications of the unit 12, the digital unit 13, and the like. In Table 1, an FIR filter is used as an example, but the present invention may be applied to an IIR filter.

For example, it is assumed that the following (1), (2), and (3) are given as request parameters in a program obtained from the outside.

(1) Modulation method = ｛π / 4 shift QPSK
(However, the root cosine roll-off characteristic with a roll-off rate of 0.5) {(2) Signal transmission rate = {1024 kbps} (3) Adjacent channel leakage = {1024 kHz detuning 153}
Given that the leakage power in a 6 kHz width is -45 dBc｝, the digital section 1
3 (the number of taps, the coefficient of each tap W01 = F3h, W02 = EFh,... W2)
3 = F3h) is determined by Table 1.

[0015] Table 2 above determines the FIR filter inside the software defined radio based on information on the modulation scheme, signal transmission speed and occupied frequency bandwidth including the filter characteristics specified by the program obtained from the outside. Includes instructions for doing so. This table also includes the analog unit 11 and the ADC / DAC unit 1 that constitute the software defined radio 1.
2. It is prepared in advance for each terminal device supplied by each manufacturer based on hardware specifications of the digital unit 13 and the like.

For example, it is assumed that the following parameters (1), (2), and (4) are given as request parameters in a program obtained from the outside.

(1) Modulation method = ｛π / 4 shift QPSK
(However, the root cosine roll-off characteristic with a roll-off rate of 0.5) (2) Signal transmission speed = {1024 kbps} (4) Occupied frequency bandwidth = {768 kHz or less} Part 1
3 (the number of taps, the coefficient of each tap W01 = 00h, W02 = 11h,... W1)
5 = 00h) is determined from Table 2.

For example, in the table 141,
In a program obtained from outside, the following (1) (2)
(3) Assume that (4) is given as a request parameter.

(1) Modulation method = ｛π / 4 shift QPSK
(However, the root cosine roll-off characteristic with a roll-off rate of 0.5) {(2) Signal transmission rate = {1024 kbps} (3) Adjacent channel leakage = {1024 kHz detuning 153}
(4) Occupied frequency bandwidth = {768 kHz or less} If the occupied frequency bandwidth is {768 kHz or less}, the digital unit 1
3 (the number of taps, the coefficient of each tap W01 = F3h, W02 = EFh,... W2)
3 = F3h) is determined from Tables 1 and 2 above.

Next, an example in which the digital unit 13 utilizes the filter parameters obtained from the table 141 will be described with reference to FIGS.

A first example of use is as follows. In the software defined radio 1 shown in FIG.
This is an example of a case where a filter processing subroutine block designed so that desired filter processing can be realized only by updating parameters in advance is programmed.

Through an external device or an antenna 10,
The software program for the digital section 13 is fetched and temporarily stored in the memory section 14. The program contains information on modulation scheme, signal transmission rate, adjacent channel leakage and occupied frequency bandwidth.

As shown in FIG. 2, the download control block programmed in the DSP 131 in advance is
The sample magnification, the number of taps, and the coefficient of each tap obtained from the above program and the table 141 from the memory unit 14 are set in the filter processing subroutine block 3 programmed in advance in the DSP 131 to determine the filter processing method.

That is, in the filter processing subroutine block 3, the sampling speed of the modulation output signal from the modulation processing subroutine block is adjusted in accordance with the sample magnification determined from the table 141 by the sampling section 31.

Next, the filtering unit 32 executes a filtering process according to the number of taps determined from the table 141 and the coefficient of each tap so that the adjacent channel leakage and the occupied frequency bandwidth satisfy the requirements.
Output to C section 12.

In this application example, the filtering unit 32 may be replaced with a PLD (Programmable Logic Device) dedicated to filter processing in order to speed up the filter processing.

The second example of use is an example in a software defined radio 1 'having a code generator 15 as shown in FIG. In the software defined radio 1 ′, the source program of the software for the digital section 13 is fetched through an external device or the antenna 10 and is stored in the memory section 14.
Is temporarily stored. The above source program is a modulation method,
It contains information on signal transmission rate, adjacent channel leakage and occupied frequency bandwidth.

The code generation section 15 generates an execution program for the digital section 13 based on the source program and the table 141, and temporarily stores it in the memory section 14. The execution program is a modulation method included in the source program, a signal transmission rate, according to information about adjacent channel leakage and occupied frequency bandwidth,
It includes a filter processing routine based on the filter parameters obtained from the table 141. The DSP 131 in the digital unit 13 stores the execution program in the memory unit 1.
4 and run.

As described above, the filtering process that meets the requirements of the adjacent channel leakage and the occupied frequency bandwidth is performed.

[0030]

The software defined radio of the present invention has a table for determining parameters for determining the characteristics of the functional elements inside the software defined radio, and the radio station standard items defined by the Radio Law. Can be directly specified from an external program, and the characteristics of the internal functional elements can be determined after referring to the above table, so that the software defined radio of the present invention can comply with the Radio Law even when a new program is executed. Compliance can be assured in advance.

When the characteristics of the internal functional elements are determined after referring to the table, standard items defined by the Radio Law are used. The inclusion of this universal confirmation parameter in the program has the following side effects.

(1) When a plurality of different manufacturers supply a software radio as a terminal device, the infrastructure side needs to provide a different program for each terminal device because there is a difference in their own manufacturing know-how. It becomes an inefficient situation. However, if the software defined radio according to the present invention is applied, the above-mentioned universal fixed parameters can be used for describing the program, so that the number of parts where the program can be shared increases and the efficiency becomes higher.

(2) For a manufacturer that provides a terminal device to which the software defined radio of the present invention is applied, the above-mentioned universal fixed parameters can be used for describing a program. The need to disclose to the outside can be reduced.

In an embodiment in which the software defined radio of the present invention has a table for determining a filter inside the software defined radio, the above table specifies the adjacent channel leakage and the occupied frequency bandwidth from an external program, and the internal table specifies the filter. Therefore, even when the software defined radio of the present invention newly executes a program, it is possible to guarantee in advance the power leaking to the adjacent channel and the occupied frequency bandwidth of the signal power. .

From the above table, it is possible to know necessary filter taps according to the external program.
By executing the filtering process using the required filter taps, it is possible to suppress waste of power consumption. Further, when specifying the filter parameters from the above table, parameters having high universality such as a modulation method, a signal transmission speed, adjacent channel leakage, and an occupied frequency bandwidth are used. This makes it possible to reduce the difference between the types of programs provided by the infrastructure side for each model. In addition, for a manufacturer providing a terminal device to which the software defined radio of the present invention is applied, the technology for building hardware is disclosed to the outside. The need to do so can also be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a software defined radio according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an example of setting a filter parameter according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a software defined radio according to another embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional software defined radio.

[Explanation of symbols]

1, software radio, 10 antenna, 11
Analog section, 12 ADC / DAC section, 13 Digital section, 131 DSP, 14 Memory section, 15 Code generation section, 3 Filter subroutine block, 31
... Sampling unit, 32 ... Filtering unit

Continuing on the front page (72) Inventor Koji Watanabe 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. In-house F-term (reference) 5K011 EA00 EA01 EA03 JA12 LA08 5K034 AA05 AA15 AA20 DD01 EE03 HH01 HH61

Claims (6)

[Claims] 1. A software defined radio, comprising: a table for determining parameters for determining characteristics of functional elements included in the software defined radio based on one or more standard items as external input parameters. Machine. 2. The method according to claim 1, wherein at least a modulation method, a signal transmission rate, a definition of an adjacent channel, and a permissible leakage power to the adjacent channel are used as external input parameters. 2. The software defined radio according to claim 1, further comprising a table for determining the sample magnification, the number of filter taps, and the coefficient of each tap. 3. The method according to claim 1, wherein at least the modulation method, the signal transmission rate, the definition of the adjacent channel, and the allowable leakage power to the adjacent channel are used as external input parameters, and the occupied frequency bandwidth of the transmission signal is used as an input parameter. 3. The software defined radio according to claim 2, further comprising a table for determining a sample magnification, a filter tap number, and a coefficient of each tap in the software defined radio at the time of filtering in accordance with the parameter. 4. A DSP included in the software defined radio.
3. The software defined radio according to claim 2, wherein a digital signal processor is programmed with a filter processing subroutine block designed to realize a desired filter processing only by updating parameters in advance. 5. A PLD (Programmable) designed so that a desired filtering process can be realized only by updating parameters in advance in a digital section included in the software defined radio.
3. A Logic Device).
Software radio described. 6. A software program for execution based on a sample magnification, a filter tap number, and a coefficient of each of said taps in a software radio, which is determined by a table provided in said radio from said source program. 3. The software defined radio according to claim 2, further comprising a code generator for generating a program.