JP2006135707A - Software wireless device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems in prior arts and to provide a wireless communication device capable of increasing transmission rate while restraining expansion of a hardware scale. <P>SOLUTION: A software wireless device comprises multiple orthogonal modulation/demodulation units 21a, 21b, 21c and 21d; a baseband processor 23; multiple buses 22 for connecting the orthogonal modulation/demodulation units to the baseband processor; an antenna unit 11 for sending/receiving wireless signals; a communication control unit 24 for managing softwares in the orthogonal modulation/demodulation units and the baseband processor, and controlling the orthogonal modulation/demodulation units and the baseband processor. The communication control unit allocates the bus to be used in accordance with a modulation method, and the orthogonal modulation/demodulation units and the baseband processor switch the bus to be used in accordance with an instruction from the communication control unit. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a software defined radio.

  In recent years, various frequency bands have been used due to significant advances in wireless communication hardware and software technologies, ultra-high density and high functionality of communication ICs and LSIs, and the rapid spread of wireless terminal devices such as mobile phones. Many modulation schemes have been devised, and various hardware corresponding to the modulation schemes are provided. In addition, in order to effectively use limited frequency resources, the development of new frequency bands and the development of new modulation schemes will progress, and the types of wireless communication hardware will continue to increase.

  However, in the conventional wireless communication apparatus using hardware, a wireless communication apparatus corresponding to the modulation method is required. Further, when a plurality of modulation schemes are used, it is common that as many radio communication apparatuses as the number of modulation schemes are required.

  For wireless communication devices with a fixed modulation method as described above, in order to cope with unknown modulation methods that will continue to increase in the future, common wireless communication hardware is used and software implemented on the hardware A “software radio” that switches the modulation scheme to be applied has been developed by appropriately changing. In the case of a software defined radio, hardware is commonly used, and processing related to a modulation method is generally realized in the form of digital signal processing software in a signal processing unit. For this reason, the physical size does not increase even if the number of modulation schemes handled increases, and it becomes possible to flexibly cope with the addition or change of software even when adding functions or changing parameters.

  An apparatus that processes a plurality of modulation schemes with common hardware, such as the above-described software defined radio, has adjustment points, that is, modulation / demodulation parameters according to the modulation schemes. By performing this adjustment by software processing, it is possible to flexibly control a plurality of modulation schemes. In addition, the data transmission rate to be transmitted / received varies depending on the modulation method, but the transmission rate to be used can be flexibly changed by changing the modulation / demodulation processing software, changing the modulation / demodulation parameter, or reconfiguring.

  FIG. 18 is a block diagram showing an example of the configuration of a conventional software defined radio. 18 includes an antenna unit 11, a high-frequency unit 12, a plurality of orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d, a data transmission bus unit 122, a baseband processing unit (BB processing unit) 123, an I / O unit 13 and communication control unit 124 are provided. This is an example of a software defined radio when a single baseband processing unit 123 realizes baseband processing of a plurality of wireless channels.

  The data transmission bus unit 122 selects an orthogonal modulation / demodulation unit connected to the baseband processing unit 123 in accordance with an instruction from the communication control unit 124. The communication control unit 124 exchanges control signals with each unit in order to control each unit. In addition, according to instructions from the user, it notifies each section of information such as a modulation method, and also has a function of transferring data files such as necessary software and parameters. It also has a function of receiving notification of real-time information (in use, alarm, warning, etc.) from each unit and notifying the user.

  At the time of transmission, transmission data input from an external device to the I / O unit 13 is subjected to modulation signal processing by the baseband processing unit 123, and the obtained baseband transmission signals are converted into orthogonal modulation / demodulation units 121a, 121b, 121c, The data is transmitted to the one designated by the communication control unit 124 through the data transmission bus unit 122. The output from the baseband processing unit 123 is subjected to orthogonal modulation processing in the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d, converted into a desired frequency in the high frequency unit 12, and wirelessly transmitted from the antenna unit 11.

  At the time of reception, the radio signal is wirelessly received by the antenna unit 11, converted to a desired frequency by the high frequency unit 12, and subjected to orthogonal demodulation processing by the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d as a baseband reception signal. The data is output to the data transmission bus unit 122. A baseband received signal from the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d designated by the communication control unit 124 is selected by the data transmission bus 122 and demodulated signal processing is performed by the baseband processing unit 123. The received data is output from the I / O unit 13 to the external device.

  The communication control unit 124 acquires and stores software necessary for modulation / demodulation by communicating with an external device. Also, modulation processing software and demodulation processing software are provided to the baseband processing unit 123 and the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d. For this reason, it includes a storage for storing software and a processor such as a CPU for controlling, and is loaded with software and applications such as an OS.

  The baseband processing unit 123 is generally composed of a programmable device such as an FPGA or DSP in order to execute modulation / demodulation processing according to the modulation method, and can be used by changing software as necessary.

  FIG. 19 is a block diagram showing another example of the configuration of a conventional software defined radio. 19, the same reference numerals as those in FIG. 18 denote the same or corresponding parts as those in FIG. 18, and a description thereof will be omitted here. The software defined radio in FIG. 19 includes orthogonal modulation / demodulation units 131a, 131b, 131c, and 131d instead of the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d, and a data transmission bus unit 132 instead of the data transmission bus unit 122. And baseband processing units 133 a, 133 b, 133 c, and 133 d instead of the baseband processing unit 123, and a communication control unit 134 instead of the communication control unit 124. This is an example of a software defined radio when one baseband processing unit is assigned to one orthogonal modulation / demodulation unit.

  The orthogonal modulation / demodulation unit 131a and the baseband processing unit 133a, the orthogonal modulation / demodulation unit 131b and the baseband processing unit 133b, the orthogonal modulation / demodulation unit 131c and the baseband processing unit 133c, and the orthogonal modulation / demodulation unit 131d and the baseband processing unit 133d are a data transmission bus unit. 132 are connected to each other.

  The operation at the time of transmission is the same as that in the example of FIG. 18, but the outputs of the baseband processing units 133a, 133b, 133c, and 133d are transmitted through the data transmission bus unit 132 to the corresponding quadrature modulation / demodulation units 131a, 131b, 131c, The difference is that it is transmitted to 131d. The operation at the time of reception is the same as that of the example of FIG. 18, but the outputs of the orthogonal modulation / demodulation units 131a, 131b, 131c, and 131d are transmitted through the data transmission bus unit 132 to the corresponding baseband processing units 133a, 133b, 133c, It is different in that it is transmitted to 133d.

As a related art related to the present invention, for example, a technique of performing relay while switching between different modulation schemes using a software defined radio (for example, see Patent Document 1) has been proposed.
JP 2003-174394 A (pages 7-13, FIG. 1)

  However, the upper limit of the transmission rate that can be realized by a software defined radio is largely dependent on hardware such as arithmetic processing performance such as CPU and DSP, data transmission bus width, and operation clock frequency. In addition, since there is a limit on the transmission rate between the internal functional blocks, the transmission rate that can be realized may be limited. For this reason, there are cases where a desired transmission rate cannot be achieved even by changing only the software executing the modulation / demodulation processing on the common hardware.

  In addition, since the software defined radio as described above has the same hardware and changes only the software to realize various modulation schemes, the quadrature modulation / demodulation units have a common specification. In addition, since the respective wireless channels function equally, specifications such as the bus size of the data transmission bus unit are equally fixed, so that the bus size becomes a bottleneck of the transmission rate. Here, only the data transmission bus unit between the quadrature modulation / demodulation unit and the baseband processing unit is described. However, this can be applied to any part as long as it transmits data signals and control signals. Can occur.

  This problem can be solved by increasing the size or performance of the hardware. However, there is a demand for downsizing and lower prices of wireless communication devices, and transmission efficiency without increasing the size and cost of the hardware. It is demanded to improve.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a wireless communication apparatus that realizes an increase in transmission rate while suppressing an increase in hardware scale.

  In order to solve the above-described problems, the present invention provides a plurality of orthogonal modulation / demodulation units that perform orthogonal modulation or demodulation by software, a single baseband processing unit that performs baseband modulation or baseband demodulation by software, A plurality of buses connecting the orthogonal modulation / demodulation unit and the one baseband processing unit, an antenna unit connected to the orthogonal modulation / demodulation unit and transmitting / receiving a radio signal, software of the orthogonal modulation / demodulation unit, and the baseband processing unit A software defined radio including a communication control unit that controls the orthogonal modulation / demodulation unit and the baseband processing unit, wherein the communication control unit is a bus used in accordance with a modulation scheme. And instructing the orthogonal modulation / demodulation unit and the baseband processing unit to use the bus, The baseband processing section and the 交変 demodulator is characterized in that to switch the bus to be used according to an instruction from the communication control unit.

  The present invention also includes a plurality of orthogonal modulation / demodulation units that perform orthogonal modulation or orthogonal demodulation by software, a baseband processing unit that performs baseband modulation or baseband demodulation by software, and the orthogonal A bus connecting the modulation / demodulation unit and the corresponding baseband processing unit, an antenna unit connected to the orthogonal modulation / demodulation unit for transmitting and receiving radio signals, software for the orthogonal modulation / demodulation unit, and software for the baseband processing unit A software defined radio including a communication control unit that manages and controls the orthogonal modulation / demodulation unit and the baseband processing unit, wherein the communication control unit assigns a bus direction, and The baseband processing unit is instructed in the direction of the bus, and the quadrature modulation / demodulation unit and the baseband are instructed. Processing unit is characterized in that for switching the direction of the bus in accordance with an instruction from the communication control unit.

  Note that the antenna portion refers to the antenna portion in the embodiment, or the antenna portion and the high-frequency portion.

  According to the present invention, it is possible to employ a modulation method with a high transmission rate compared to the case where a fixed data transmission bus is used, and it is possible to use hardware more adaptively and operate efficiently. A simple software defined radio.

  Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing an example of the configuration of a software defined radio according to the present invention. In FIG. 1, the same reference numerals as those in FIG. 18 denote the same or corresponding parts as those in FIG. 18, and the description thereof is omitted here. 1 includes orthogonal modulation / demodulation units 21a, 21b, 21c, and 21d instead of the orthogonal modulation / demodulation units 121a, 121b, 121c, and 121d, and a data transmission bus unit 22 instead of the data transmission bus unit 122. A baseband processing unit 23 instead of the baseband processing unit 123, and a communication control unit 24 instead of the communication control unit 124.

  The user of the software defined radio of the present invention can add a channel and select a modulation method by setting the communication control unit 24 if there is an empty channel. In addition, the user can make the channel unused in the same manner. Here, a method of adding a channel and selecting a modulation scheme will be described.

  The communication control unit 24 includes a modulation method parameter table, a channel use status register, a bus use status register, and a settable method table. FIG. 2 is a table showing an example of a modulation scheme parameter table according to the present invention. In the modulation scheme parameter table, a data transmission rate, the number of buses to be occupied, a filtering coefficient, the number of taps, and the like are defined for each modulation scheme. This table shows some of these parameters. Further, the communication control unit 24 sets a modulation scheme that can be additionally set by monitoring a channel usage status register that stores the usage status of each channel and a bus usage status register that stores the usage status of each bus. Create as possible method table. FIG. 3 is a table showing an example of the channel usage status register according to the present invention. FIG. 4 is a table showing an example of the bus usage status register according to the present invention. FIG. 5 is a table showing an example of a settable modulation scheme table according to the present invention.

  The communication control unit 24 guides the user to select a modulation method shown in the settable modulation method table, or pays attention to the user when the user selects a modulation method that is not in the settable modulation method table. Prompt.

  For example, only the modulation method F or the modulation method G can be selected in the state of the settable modulation method table shown in FIG. Here, when the user wants to perform communication using the modulation method B, according to FIG. 2, since the two buses are used, the user first sets the currently used channel 1 to the unused state. This state is shown in the figure. FIG. 6 is a table showing another example of the channel usage status register according to the present invention. FIG. 7 is a table showing another example of the bus usage status register according to the present invention. FIG. 8 is a table showing another example of the settable modulation scheme table according to the present invention. When channel 1 is set to an unused state as shown in the channel usage status register of FIG. 6, the bus 1 becomes unused as shown in the bus usage status register of FIG. 7, and as shown in the settable modulation method table of FIG. Modulation method A and modulation method B are added to the settable modulation method, and the user can add a channel of modulation method B.

  Next, the communication control unit 24 performs bus selection for the modulation scheme requested by the user. FIG. 9 is a flowchart showing an example of bus selection operation in the communication control unit according to the present invention. First, the communication control unit determines whether there is a request for a modulation scheme to be added from the user (S11). If there is no request (S11, N), the process returns to S11. Next, the settable modulation method table is referred to (S12), and it is determined whether or not the requested modulation method corresponds to the settable modulation method (S21). If the requested modulation method is not applicable (S21, N), the user is notified that setting is not possible (S22), and this flow ends. On the other hand, if the requested modulation method is applicable (S21, Y), the channel usage status register and the bus usage status register are referred to (S31), and the requested modulation is performed according to the bus priority set in advance for each bus. The bus and channel are assigned to the system (S32), and this flow is finished.

  Next, details of the configuration for switching the bus will be described. FIG. 10 is a block diagram showing an example of a configuration for bus switching according to the present invention. Here, details of the orthogonal modulation / demodulation unit 21a, the data transmission bus unit 22, and the baseband processing unit 23 are shown. Here, the data transmission bus unit 22 and the baseband processing unit 23 show only a part connected to one orthogonal modulation / demodulation unit 21a, but the same configuration is applied to the other three orthogonal modulation / demodulation units 21b, 21c, and 21d. have.

  The orthogonal modulation / demodulation unit 21 a includes an orthogonal modulation unit 41, an orthogonal demodulation unit 42, a bus switching unit 43, and an orthogonal modulation / demodulation control unit 44. The baseband processing unit 23 includes a baseband modulation unit (BB modulation unit) 51, a baseband demodulation unit (BB demodulation unit) 52, a bus switching unit 53, and a baseband processing control unit (BB processing control unit) 54. . The data transmission bus unit 22 includes four buses, a bus 1, a bus 2, a bus 3, and a bus 4 that connect the orthogonal modulation / demodulation unit 21 a and the baseband processing unit 23. Of these, bus 1 and bus 2 are used for transmission, and bus 3 and bus 4 are used for reception.

  The communication control unit 24 passes control signals such as the modulation scheme software and parameters used and the bus used to the orthogonal modulation / demodulation control unit 44 and the baseband processing control unit 54. The quadrature modulation / demodulation control unit 44 controls the modulation scheme of the quadrature modulation unit 41, the demodulation scheme of the quadrature demodulation unit 42, and the switch of the bus switching unit 43 according to the control signal from the communication control unit 24. Similarly, the baseband processing control unit 54 controls the modulation method of the baseband modulation unit 51, the demodulation method of the baseband demodulation unit 52, and the input / output of the bus switching unit 53 in accordance with instructions from the communication control unit 24. During reception, the output of the orthogonal demodulator 42 is input to the baseband demodulator 52 through the bus selected by the bus switch 43 and the bus switch 53. During transmission, the output of the baseband modulation unit 51 is input to the quadrature modulation unit 41 through the bus selected by the bus switching unit 53 and the bus switching unit 43.

  Next, a case where one modulation / demodulation processing unit and the baseband processing unit 23 use two buses will be described. Here, the flow of data at the time of reception will be described, but the same applies at the time of transmission. FIG. 11 is a table showing an example of data at the time of reception by the data transmission bus unit according to the present invention. First, the orthogonal demodulator 42 sequentially outputs data D0, D1, D2, and D3. Next, the bus switching unit 43 performs serial-parallel conversion, so that the bus 3 sequentially transmits the data D0 and D2 and the bus 4 sequentially transmits the data at a transmission rate that is half the output data of the orthogonal demodulation unit 42. D1 and D3 are transmitted. Next, when the bus switching unit 53 performs parallel-serial conversion, the baseband demodulating unit 52 sequentially receives the data D0, D1, D2, and D3 at the transmission rate of the output data of the original orthogonal demodulating unit 42. To do. That is, the maximum value of the transmission rate between one modulation / demodulation processing unit and the baseband processing unit 23 can be double the bus transmission rate by using two buses.

  Next, a specific example of bus selection will be described. FIG. 12 is a block diagram showing a first example of bus selection according to the first embodiment. In this example, one bus is used for reception in the orthogonal modulation / demodulation unit 21a, one bus is used for transmission in the orthogonal modulation / demodulation unit 21b, and one bus is used for reception in the orthogonal modulation / demodulation unit 21c. One bus is used for transmission in the orthogonal modulation / demodulation unit 21d. Therefore, in this example, there are four communication systems that can be used for transmission or reception, and the maximum value of the transmission rate between each of the orthogonal modulation / demodulation units 21a, 21b, 21c, and 21d and the baseband processing unit 23 is the bus This is the transmission rate.

  FIG. 13 is a block diagram showing a second example of bus selection according to the first embodiment. In this example, two buses are used for reception in the orthogonal modulation / demodulation unit 21a, and two buses are used for transmission in the orthogonal modulation / demodulation unit 21b. Therefore, in this example, the number of usable communication systems that can be used for transmission or reception is reduced from four to two, but the maximum value of the transmission rate between each of the orthogonal modulation / demodulation units 21a and 21b and the baseband processing unit 23 is , Twice the bus transmission rate.

Embodiment 2. FIG.
FIG. 14 is a block diagram showing another example of the configuration of the software defined radio according to the present invention. 14, the same reference numerals as those in FIG. 1 denote the same or corresponding parts as those in the drawing, and the description thereof is omitted here. The software defined radio in FIG. 14 includes orthogonal modulation / demodulation units 31a, 31b, 31c, and 31d instead of the orthogonal modulation / demodulation units 21a, 21b, 21c, and 21d, and a data transmission bus unit 32 instead of the data transmission bus unit 22. Instead of the baseband processing unit 23, baseband processing units 33 a, 33 b, 33 c and 33 d are provided, and a communication control unit 34 is provided instead of the communication control unit 24.

  In the present embodiment, the orthogonal modulation / demodulation unit 31a and the baseband processing unit 33a are connected by a single bus by the data transmission bus unit 32, and the orthogonal modulation / demodulation unit 31b and the baseband processing unit 33b are connected by a single bus. The orthogonal modulation / demodulation unit 31c and the baseband processing unit 33c are connected by a single bus, and the orthogonal modulation / demodulation unit 31d and the baseband processing unit 33d are connected by a single bus. That is, one baseband processing unit is connected to one orthogonal modulation / demodulation unit by one bus. The communication control unit 34 controls the method of using the bus of the data transmission bus unit 32 and controls the modulation method in the orthogonal modulation / demodulation units 31a, 31b, 31c, 31d and the baseband processing units 33a, 33b, 33c, 33d.

  Next, a specific example of bus selection will be described. FIG. 15 is a block diagram illustrating a first example of bus selection according to the second embodiment. In this example, each bus in the data transmission bus unit 32 is used in a time division manner for both transmission and reception. Therefore, in this example, the number of communication systems that can be transmitted and received is four. However, if transmission and reception are used in equal time intervals, the maximum transmission rate of these communication systems is the bus transmission rate. It becomes half.

  FIG. 16 is a block diagram illustrating a second example of bus selection according to the second embodiment. In this example, the bus connecting the orthogonal modulation / demodulation unit 31a and the baseband processing unit 33a is used for transmission, the bus connecting the orthogonal modulation / demodulation unit 31b and the baseband processing unit 33b is used for reception, and the orthogonal modulation / demodulation unit 31c. And the baseband processing unit 33c are used for transmission, and the bus connecting the quadrature modulation / demodulation unit 31d and the baseband processing unit 33d is used for reception. Therefore, although there are two communication systems that can transmit and receive, the maximum transmission rate of these communication systems is the bus transmission rate.

  FIG. 17 is a block diagram illustrating a third example of bus selection according to the second embodiment. In this example, one set of orthogonal modulation / demodulation units 31a and 31b and one set of baseband processing units 33a and 33b are assigned and transmission processing of one communication system is assigned. Also, one set of orthogonal modulation / demodulation units 31c and 31d and one set of baseband processing units 33c and 33d are assigned to receive processing of one communication system. The bus connecting the quadrature modulation / demodulation unit 31a and the baseband processing unit 33a and the bus connecting the quadrature modulation / demodulation unit 31b and the baseband processing unit 33b are used for transmission, and connects the quadrature modulation / demodulation unit 31c and the baseband processing unit 33c. The bus and the bus connecting the orthogonal modulation / demodulation unit 31d and the baseband processing unit 33d are used for reception. Therefore, although there is one communication system that can transmit and receive, the maximum transmission rate of this communication system is twice that of the bus.

  As described above, the hardware can be efficiently used by setting the modulation method, channel, and bus in the communication control unit. Furthermore, by constructing a bundle of buses and realizing a transmission rate that exceeds the transmission rate of a single bus, the transmission rate of wireless communication can be improved without increasing the circuit scale.

  Here, the configuration for selecting the signal line in the data transmission bus unit between the quadrature modulation / demodulation unit and the baseband processing unit has been described. However, the same effect can be obtained by selecting a signal line for transmitting other signals. Is obtained.

It is a block diagram which shows an example of a structure of the software defined radio concerning this invention. It is a table | surface which shows an example of the modulation system parameter table which concerns on this invention. It is a table | surface which shows an example of the channel use condition register which concerns on this invention. It is a table | surface which shows an example of the bus usage condition register | resistor based on this invention. It is a table | surface which shows an example of the configurable modulation system table which concerns on this invention. It is a table | surface which shows another example of the channel usage condition register which concerns on this invention. It is a table | surface which shows another example of the bus usage condition register | resistor based on this invention. It is a table | surface which shows another example of the configurable modulation system table which concerns on this invention. It is a flowchart which shows an example of the operation | movement of bus selection in the communication control part which concerns on this invention. It is a block diagram which shows an example of the structure for the bus switching which concerns on this invention. It is a table | surface which shows an example of the data at the time of reception of the data transmission bus part which concerns on this invention. 6 is a block diagram showing a first example of bus selection according to the first embodiment. FIG. 6 is a block diagram showing a second example of bus selection according to Embodiment 1. FIG. It is a block diagram which shows another example of a structure of the software defined radio concerning this invention. FIG. 10 is a block diagram showing a first example of bus selection according to the second embodiment. FIG. 10 is a block diagram showing a second example of bus selection according to the second embodiment. FIG. 10 is a block diagram illustrating a third example of bus selection according to the second embodiment. It is a block diagram which shows an example of a structure of the conventional software defined radio. It is a block diagram which shows another example of a structure of the conventional software defined radio.

Explanation of symbols

11 antenna unit, 12 high frequency unit, 13 I / O unit, 21a, 21b, 21c, 21d, 31a, 31b, 31c, 31d, 121a, 121b, 121c, 121d, 131a, 131b, 131c, 131d orthogonal modulation / demodulation unit, 22 , 32, 122, 132 Data transmission bus unit, 23, 33a, 33b, 33c, 33d, 123, 133a, 133b, 133c, 133d Baseband processing unit, 24, 34, 124, 134 Communication control unit, 41 Quadrature modulation unit , 42 Quadrature demodulation unit, 43, 53 Bus switching unit, 44 Quadrature modulation / demodulation control unit, 51 Baseband modulation unit, 52 Baseband demodulation unit, 54 Baseband processing control unit.

Claims (1)

A plurality of orthogonal modulation / demodulation units that perform orthogonal modulation or demodulation by software;
One baseband processing unit for performing baseband modulation or baseband demodulation by software;
A plurality of buses connecting each of the orthogonal modulation / demodulation units and one of the baseband processing units;
An antenna unit connected to the orthogonal modulation / demodulation unit for transmitting and receiving radio signals;
Managing the software of the quadrature modulation / demodulation unit and the software of the baseband processing unit, and a communication control unit for controlling the orthogonal modulation / demodulation unit and the baseband processing unit,
A software defined radio comprising:
The communication control unit assigns a bus to be used according to a modulation scheme, and instructs the orthogonal modulation / demodulation unit and the baseband processing unit to use the bus,
The quadrature modulation / demodulation unit and the baseband processing unit switch a bus to be used according to an instruction from the communication control unit.

Images