JP4624253B2 - Communication device and communication system - Google Patents

Description

The present invention relates to a communication apparatus that multiplexes and communicates a plurality of different frequencies, a circuit configuration of a communication apparatus that communicates using a single frequency, and an improvement of the communication system.

When communication is performed using a single frequency, a phenomenon called fading in which the intensity of the received electric field fluctuates with time due to various factors in the radio wave propagation path appears. Fading has a short period of several hundreds of ms to a period of several hours, and is one of the major factors that degrade the communication quality of wireless communication. Actually, fading often occurs due to a plurality of factors overlapping.
In order to maintain communication quality from fading, a communication method for communicating at a plurality of frequencies has been proposed. For example, Patent Document 1 discloses that the frequency of a data to be superimposed on a power line is synthesized by an inverse Fourier transform circuit on the data transmitter side, and data is extracted from the signal received by the Fourier transform circuit on the receiver side. A technique is disclosed in which a plurality of communication carriers are provided on the axis, and a signal having a frequency with a small error rate is selected for transmission among the plurality of transmission carriers when data for transmission is converted by an inverse Fourier transform circuit.
In the conventional example disclosed in Patent Document 2, in the transmission apparatus, the modulation circuit modulates the subcarrier generated by the clock signal generation circuit with the transmission data string, and the impulse string signal generation circuit generates the impulse string signal as the carrier signal. The frequency conversion circuit converts the frequency of the carrier signal, which is an impulse train signal, and transmits it from the antenna. In the receiving apparatus, the frequency conversion circuit converts the frequency of the reception signal with the impulse string signal, the intermediate frequency filter circuit extracts the intermediate frequency signal, and the demodulation circuit demodulates it to output the reception data string.

JP 2000-165304 A Japanese Patent Laid-Open No. 11-341086

However, in the conventional technique disclosed in Patent Document 1, the transmitter side generates a transmission signal by an inverse Fourier transform circuit, and the receiver side extracts data from the signal received by the Fourier transform circuit, thereby generating a frequency. A plurality of communication carriers are provided on the shaft. In other words, this conventional technique requires a function for performing inverse Fourier transform and Fourier transform, and requires hardware such as dedicated hardware (ASIC) and DSP for realizing high-speed product-sum operation. There was a problem that it was costly and could not be easily realized.

Further, in the prior art disclosed in Patent Document 2, the carrier signal is frequency-converted and transmitted from the antenna, and the reception side is frequency-converted and demodulated with the impulse train signal on the reception side. There is a problem that the configuration becomes complicated.
In view of such a problem, the present invention provides a communication device that multiplexes and communicates a plurality of different frequencies, multiplexes a plurality of different frequencies on the transmission side, modulates the transmission data, and receives signals from the multiplexed carriers on the reception side. It is an object of the present invention to provide a communication apparatus that can realize a low-cost circuit configuration that is resistant to carrier noise and fading by extracting the received data and demodulating received data.
Another object is to communicate by using a plurality of different frequencies or a single frequency, and at the time of transmission, the frequency is sequentially lowered until a response signal from another communication device is recognized. Is to provide a communication system that is resistant to carrier noise and fading by continuing the subsequent communication based on the frequency at the time of recognition.

In order to solve such a problem, the present invention is a communication device that includes a transmission device and a reception device and performs communication by multiplexing a plurality of different frequencies, and the transmission device includes first oscillation means that oscillates a fundamental frequency, and A second oscillating means for dividing the oscillation output signal oscillated by the first oscillating means by a predetermined frequency dividing ratio; and the respective oscillating output signals outputted by the first oscillating means and the second oscillating means. And a modulator that modulates the oscillation output signal of the combining circuit with transmission data, and the receiving device has a predetermined frequency band included in a signal received from a transmitting device included in another communication device. receiving de a band-pass filter for passing the filter output signal passing through the band-pass filter and a conversion circuit for converting a logic signal, by processing the output signal outputted by the converter Obtain other.

According to the present invention, in a transmission device, an oscillation output signal output from an oscillator and a signal obtained by dividing the oscillation output signal are multiplexed and transmitted, thereby easily transmitting using a plurality of frequencies. Can do. On the receiving side, a band-pass filter that passes both the fundamental frequency of the oscillation output signal used in the transmission device and the frequency obtained by dividing the oscillation output signal, and the signal extracted through this band-pass filter By passing through a low-pass filter, it becomes possible to easily receive signals of a plurality of frequencies. This makes it possible to develop a communication system that is resistant to noise and fading at low cost.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. .

FIG. 1 is a block diagram showing a configuration of a communication system according to the present invention.
The communication system 100 illustrated in FIG. 1 illustrates a configuration example in which communication is performed by two communication devices 30a and 30b. The communication device 30a includes a transmission device 13 including an antenna 6a, a reception device 14 including an antenna 6b, and an MPU (Micro Processing Unit) 1 that controls the transmission device 13 and the reception device 14. Similarly, the communication device 30b includes a transmission device 13 provided with an antenna 6a, a reception device 14 provided with an antenna 6b, and an MPU 1 that controls the transmission device 13 and the reception device 14. That is, the communication devices 30a and 30b are communication devices having the same configuration. For example, when the communication device 30a becomes the transmission side and communicates with the communication device 30b, the transmission data 32 is transmitted from the transmission device 13 of the communication device 30a to the communication device 30b via the antenna 6a, and the antenna 6b of the communication device 30b. The receiving device 14 receives the transmission data 32 via the. Further, when the communication device 30b becomes the transmission side and communicates with the communication device 30a, the transmission data 31 is transmitted from the transmission device 13 of the communication device 30b to the communication device 30a via the antenna 6a, and the antenna 6b of the communication device 30a is transmitted. The receiving device 14 receives the transmission data 31 through the communication device 31.

In the case of a system in which communication apparatus 100 multiplexes and communicates with a plurality of different frequencies, at the time of transmission, two or more different frequencies are combined, modulated with transmission data, and transmitted. At the time of reception, a signal is extracted from a multiplexed frequency transmitted from a transmission device included in another communication device, converted into a logical signal, and received data is acquired by processing the logical signal (details will be described later). To do). Accordingly, even if one frequency is attenuated due to the influence of fading or the like, it is possible to demodulate received data by extracting a signal from the other frequency.
FIG. 2 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the first embodiment of the present invention. The same components will be described with the same reference numerals as in FIG. The transmitter 13 includes an oscillator (first oscillating means) 2 that oscillates at a fundamental frequency (70 MHz), and a frequency divider (first frequency divider) that divides the oscillation output signal 23 oscillated by the oscillator 2 by a predetermined frequency division ratio. 2 oscillating means) 3, an AND circuit (synthesizing circuit) 4 for synthesizing the oscillation output signals 23 and 22 output from the oscillator 2 and the frequency divider 3, and an oscillation output signal 24 of the AND circuit 4 as transmission data. 20 includes a modulator 5 that modulates by an antenna 20 and an antenna 6a.
The receiving device 14 includes an antenna 6b, a bandpass filter (hereinafter referred to as BPF) (bandpass filter) 7 that passes a predetermined frequency band included in a signal received from a transmitting device included in another communication device, A low-pass filter (hereinafter referred to as LPF) 9 (low-pass filter) 9 that passes a low-frequency component from a frequency component of the filter output signal that has passed through the BPF 7, and a waveform shaper that shapes the filter output signal of the LPF 9 into a logical signal ( Waveform shaping means) 11.
The MPU 1 obtains received data by processing the output signal output from the waveform shaper 11. For example, when the signal processing is performed by software, the state of the port of the MPU 1 is read at a predetermined time interval. When the low level continues N times, it is determined as “0”, and when the high level continues N times, it is determined as “1” and is taken as received data. The logic signal may be logically processed by general-purpose hardware.
Further, the circuit configuration of the modulator 5 is, for example, a 2-input AND circuit, and the output signal 24 of the AND circuit 4 input to the modulator 5 is used as transmission data 20 (“H”, “L” output from the MPU 1. The carrier wave is output or stopped by the “signal”.

  Next, the operation of the first embodiment will be described. In addition, each signal of the transmission apparatus 13 of this embodiment is processed as a digital signal. In the communication apparatus configured as shown in FIG. 2, when transmitting from one communication apparatus to another communication apparatus, when the oscillation frequency of the oscillator 2 of the transmission apparatus 13 is, for example, 70 MHz, the oscillation signal 23 is divided. When the frequency is divided by 4 in the device 3, an oscillation output signal 22 having a frequency of 17.5 MHz is output. The AND circuit 4 ANDs the 17.5 MHz oscillation output signal 22 and the 70 MHz oscillation output signal 23 to obtain an output signal 24. As will be described later, since this output signal 24 is the result of the logical product of the 17.5 MHz oscillation output signal 22 and the 70 MHz oscillation output signal 23 divided by the frequency divider 3, 70 MHz and 17. 5 MHz will be included. When a signal having these two types of frequency components is logically ANDed by the modulator 5 with the transmission data 20 from the MPU 1, a waveform 23 is output only during a period when the oscillation output signal 22 of the frequency divider 3 is at a high level. “1”, “0”, and “1” in FIG. 3 represent transmission data 20 from the MPU 1. That is, when the 17.5 MHz digital signal is logically ANDed by the AND circuit 4, the oscillation output signal 23 (70 MHz) is included in the period of this digital signal for four cycles in this example. Therefore, the output signal 24 is a continuous waveform obtained by ANDing the waveform 22 and the waveform 23. A continuous waveform obtained by ANDing the waveform 22 and the waveform 23 is transmitted from the modulator 5 during a period in which the transmission data 20 is “1”, and from the modulator 5 during a period in which the transmission data 20 is “0”. It will not be sent. That is, the carrier frequency of the modulator 5 is the output signal 24, and the output signal 24 is modulated by the transmission data 20. As described above, the basic feature of the present invention is that communication is performed by multiplexing frequencies by digital signal processing. By using this digital signal processing circuit, the circuit configuration is simplified and effects such as low cost are obtained.

  FIG. 4 is a frequency spectrum diagram when the waveform 25 of FIG. 3 is observed on the frequency axis. The vertical axis represents signal intensity and the horizontal axis represents frequency. In FIG. 4, signals 27 and 28 having frequencies of 17.5 MHz and 70 MHz are output. However, in antenna propagation or the like, some frequencies (for example, 70 MHz) may be attenuated due to fading or the like. However, since a plurality of frequencies are multiplexed and transmitted, even if a signal of one frequency is attenuated, data can be reproduced from the other signal (for example, 17.5 MHz). Can be realized.

  Next, the operation of the receiving device 14 will be described. On the reception side, a signal from a transmission device included in another communication device is received by the antenna 6b, filtered by the BPF 7, and a frequency other than the frequency transmitted from the transmission device is cut. Thereafter, the LPF 9 is passed to generate the envelope 20 of this signal. In order to shape the waveform after passing through the LPF 9, the waveform is digitized using the waveform shaper 11 including a Schmitt buffer or a comparator, and the data is captured in the MPU 1 and demodulated. By constructing a communication system composed of such a transmission device and a reception device, it is possible to obtain a communication system that is resistant to fading with an inexpensive circuit configuration.

As described above, according to the first embodiment, in a communication apparatus that communicates using a plurality of different frequencies, at the time of transmission, the transmission apparatus modulates a plurality of different frequencies with transmission data, and at the time of reception. Since each signal is extracted by the receiving device and converted into a logical signal, and this logical signal is processed to obtain received data, even if one frequency is attenuated by fading, the other signal is extracted. Received data can be demodulated.
The transmitter 13 synthesizes the oscillation output signal 23 having the fundamental frequency and the oscillation output signal 22 obtained by dividing the signal by a predetermined division ratio, and modulates the synthesized oscillation output signal 24 with the transmission data 20. To send. The receiving device 14 passes only a predetermined frequency band from a signal received from a transmitting device included in another communication device, and converts the signal into a logic signal. Since this logic signal is input to the MPU 1 and logically processed by software to obtain received data, the apparatus can be configured with a simple circuit configuration and at a low cost. The logic signal may be logically processed by general-purpose hardware.
FIG. 5 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the second embodiment of the present invention. The same components will be described with the same reference numerals as in FIG. Since this transmission apparatus 13 has the same configuration as that shown in FIG.
The reception device 14 includes a BPF (first bandpass filter) 7 that passes 70 MHz (first frequency band) included in a signal received from a transmission device included in another communication device, and transmission included in the other communication device. BPF (second band pass filter) 8 that passes 17.5 MHz (second frequency band) included in the signal received from the device, and low frequency components from the frequency components of the filter output signal that passed BPF 7 and BPF 8 LPF 9 and LPF 10 to be passed, and waveform shapers 11 and 12 for shaping the filter output signal into a logical signal.
The MPU 1 can obtain received data by processing the output signals output from the waveform shapers 11 and 12. For example, as a signal processing method of the MPU 1, first, the state of the port is read at a predetermined time interval. In order to distinguish between the output signal output from the waveform shaper 11 and noise, the data obtained by continuously detecting “1” N times is determined as “1”, and the data is stored in the primary buffer. Data obtained by continuously detecting “0” N times is determined as “0”, and the data is stored in the primary buffer to obtain received data. Similarly, the output signal of the waveform shaper 12 is processed and stored in the primary buffer to obtain received data. Next, when 1 byte is stored in the primary buffer, it is compared whether or not the preamble data in the primary buffer matches the preamble pattern. If they match, the data is taken into the secondary buffer. Then, it is compared whether the FCC code generated from the secondary buffer matches the value of the FCC at the end of the secondary buffer. Receive.
As described above, in the method of the first embodiment, the BPF 7 on the reception side is formed by one BPF and has a wide band. Therefore, even when the transmission side is not transmitting, the noise on the antenna etc. Therefore, it is possible that the reception is judged after passing through the BPF 7. That is, the received signal may be observed even when the logic “0” in FIG. 3 is transmitted. In order to increase the resistance against such noise, BPFs 7 and 8 corresponding to signals of two frequencies to be transmitted are prepared as shown in FIG.
As described above, according to the second embodiment, the receiving device 14 of the present invention separates the signal received from the transmitting device included in the other communication device into the first and second frequency bands and converts them into logic signals. . Since these two types of logic signals are input to the MPU 1 and logically processed by software to obtain received data, the received data can be detected more accurately by comparing the two input signals. The logic signal may be logically processed by general-purpose hardware.

FIG. 6 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the third embodiment of the present invention. The same components will be described with the same reference numerals as in FIG. Since this transmission apparatus 13 has the same configuration as that shown in FIG.
The reception device 14 includes a BPF (first bandpass filter) 7 that passes 70 MHz (first frequency band) included in a signal received from a transmission device included in another communication device, and transmission included in the other communication device. BPF (second band pass filter) 8 that passes 17.5 MHz (second frequency band) included in the signal received from the device, and low frequency components from the frequency components of the filter output signal that passed BPF 7 and BPF 8 LPF 9 and LPF 10 to be passed through, waveform shapers 11 and 12 for shaping the filter output signal into a logic signal, and an AND circuit (logical product circuit) 61 for ANDing the output signals output from the waveform shapers 11 and 12 And an OR circuit (logical sum circuit) 62 that logically sums the output signals output from the waveform shapers 11 and 12.
The MPU 1 processes the output signals output from the waveform shapers 11 and 12, the AND circuit 61, and the OR circuit 62. By doing in this way, even when the waveform is strong against fading and the waveform is often missing, output data supplemented with both frequencies can be obtained from the output of the OR circuit 62, and there is a lot of noise. When it is difficult to detect the logic “0”, by receiving the output of the AND circuit 61, it is possible to remove noise components that are not output simultaneously from both frequency bands.

  The above explanation is for carrier waves having two different frequencies. However, by preparing a plurality of frequency dividers, it is possible to generate (number of frequency dividers + 1) carriers. It is clear.

  As described above, according to the third embodiment, the receiving device 14 of the present invention calculates the logical product and logical sum of the output signals of the respective waveform shapers 11 and 12, and outputs the respective output signals and the waveform shapers 11, 12. Since 12 output signals are input to MPU1 and logically processed by software to obtain received data, output data that is strong against fading and compensates at both frequencies from the ORed output even if the waveform is often missing. If there is a lot of noise and it is difficult to detect logical “0”, it is possible to remove the noise component that is not output simultaneously from both frequencies by receiving the logically output. The logic signal may be logically processed by general-purpose hardware.

  FIG. 7 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the fourth embodiment of the present invention. The same components will be described with the same reference numerals as in FIG. The transmitter 13 of the present invention includes an oscillator 2 that oscillates at a fundamental frequency (70 MHz), a programmable counter (oscillating means) 15 that can arbitrarily set a frequency division ratio of an oscillation output signal oscillated by the oscillator 2, and a programmable counter. And a modulator 5 that modulates the oscillation output signal output by the transmission data 20.

Further, the reception device 14 has a BPF 7 that passes a predetermined frequency band included in a signal received from a transmission device included in another communication device, and an LPF 10 that passes a low-frequency component from the frequency components of the filter output signal that has passed through the BPF 7. , And a waveform shaper 11 that shapes the filter output signal of the LPF 10 into a logic signal. The antennas 6a and 6b are omitted.
This communication device includes a transmission device 13 and a reception device 14. The transmission device 13 changes the frequency of the oscillator 2 using a programmable counter 15, and modulates data using this carrier wave. For example, in the transmission device 13, the basic oscillation frequency of the oscillator 2 is divided by using the programmable counter 15, such as dividing by 2, dividing by 3,. Using the divided rectangular wave as a carrier wave, the modulator 5 modulates the transmission data 20. The modulator 5 is configured by a circuit that ANDs the carrier wave and the transmission data 20 from the MPU 1. That is, when the data from the MPU 1 is “0”, there is no carrier wave, and when the transmission data is 1, the carrier wave exists.

The receiving device 14 is composed of BPF 7 and LPF 10 in the frequency range of the carrier wave set by the programmable counter 15, and has the same configuration as the receiving device in FIG.
As described above, according to the fourth embodiment, the transmission device 13 modulates and transmits the oscillation output signal obtained by dividing the oscillation output signal of the fundamental frequency by the division ratio of the value set from the outside with the transmission data 20. . The receiving device 14 passes the frequency band of the oscillation output signal from the signal received from the transmitting device included in the other communication device, and converts the signal into a logical signal. Since this logic signal is input to the MPU 1 and logically processed by software to obtain received data, as a communication method in this case, the transmitting device 15 can receive the response signal returned from the other receiving device immediately before receiving the programmable counter 15. The division ratio of the programmable counter 15 can be determined so as to be the oscillation output signal output from. The logic signal may be logically processed by general-purpose hardware.

  FIG. 8 is a sequence diagram illustrating a case where communication is performed between terminal A and terminal B using the communication apparatus of FIG. In the communication apparatus of FIG. 7, since the frequency of the carrier wave transmitted simultaneously is one type, it is easily affected by fading. Therefore, in the communication system of the present invention, first, the terminal A transmits a frame to be transmitted to the terminal B at the frequency f1, and if the response confirmation frame (ACK) from the terminal B does not arrive within a certain time, the terminal B The frame in which the value of the portion where the programmable counter value in the header in the frame is described is changed to the value of f2 (for example, “0xF2”) is transmitted at the frequency f2. (The double transmitted at the frequency of f1 is described as “0xF1”.) If the response confirmation frame (ACK) from the terminal B does not arrive within a certain time, similarly, it is displayed in the header in the frame. A frame in which the value of a part describing a certain programmable counter value is changed to the value of f3 (for example, “0xF3”) is transmitted at the frequency f3. Thus, when communication with the corresponding terminal is impossible, the frequency is switched using the programmable counter 15 and transmitted.

  On the other hand, the terminal B refers to the programmable counter value in the header portion of the received frame, sets the setting value of the programmable counter 15 to this counter value, and transmits the response confirmation frame 81. Thereby, since communication can be performed using a plurality of frequencies, a communication system that is resistant to noise and fading can be obtained.

As an example, the frame includes, as an example, a synchronization pattern “10011110” consisting of 8 bytes of PR (PREAmble), a source address SA (Source Address), and a destination address DA (Destination Address), A control code CC (Control Code), HD (Header), application data, and a frame check code, for example, an FCC (Frame Check Code) on which a CRC code is mounted.
As described above, according to this embodiment, the communication device on the transmission side starts transmission from the higher frequency, checks whether a response signal for the frequency is returned from the reception side within a predetermined time, If not returned, the frequency dividing ratio of the first oscillating means is switched to lower the frequency. This is sequentially repeated, and when the response signal is returned from the receiving side within a predetermined time, the frequency dividing ratio of the first oscillating means is determined so as to be the frequency on the transmitting side at that time. The frequency division ratio of the first oscillating means can be determined so as to be the oscillation output signal output by the first oscillating means immediately before receiving the response signal returned from the other receiving device, and the best frequency Can communicate.
FIG. 9 is a block diagram showing a configuration of a communication apparatus including a receiving apparatus according to the fifth embodiment of the present invention. In this figure, the transmission device is omitted because it is the same as the configuration of FIG. This receiving apparatus includes BPF 7a (70 MHz), 7b (35 MHz), 7c (23.3 MHz), and BPF 7a, 7b, which are provided for each predetermined frequency band included in a signal received from a transmitting apparatus included in another communication apparatus. LPFs 10a, 10b, and 10c that pass low-frequency components from the frequency components of the filter output signal that passed through 7c, waveform shapers 11a, 11b, and 11c that shape the filter output signals of LPFs 10a, 10b, and 10c into logic signals, and waveforms And an OR circuit (logical sum circuit) 91 for logically summing the output signals output from the shapers 11a, 11b, and 11c. The MPU 1 processes the output signal 92 output from the OR circuit 91 to obtain received data. In this way, by receiving through a plurality of BPFs 10a, 10b, and 10c, noise tolerance can be improved, and in the processing of MPU1, it is not necessary to observe a plurality of input ports at the same time, thereby reducing the processing load. It becomes possible to do. The antenna 9b is not shown.
As described above, according to the fifth embodiment, in order to pass the frequency band of the oscillation output signal from the signal received from the transmission device included in the other communication device, the reception device passes the BPF 7a to the frequency of the oscillation output signal. 7c, and after converting the signal into a logic signal, the respective logic signals are logically summed and input to the MPU 1 and logically processed by software to obtain received data. Therefore, the number of ports of the MPU 1 can be saved. The logic signal may be logically processed by general-purpose hardware.

FIG. 10 is a block diagram showing a configuration of a communication apparatus including a receiving apparatus according to the sixth embodiment of the present invention. In this figure, the transmission device is omitted because it is the same as the configuration of FIG. This receiving apparatus includes BPF 7a (70 MHz), 7b (35 MHz), 7c (23.3 MHz), and BPF 7a, 7b, which are provided for each predetermined frequency band included in a signal received from a transmitting apparatus included in another communication apparatus. LPFs 10a, 10b, and 10c that pass low-frequency components from the frequency components of the filter output signal that passed through 7c, waveform shapers 11a, 11b, and 11c that shape the filter output signals of LPFs 10a, 10b, and 10c into logic signals, and waveforms OR circuit (OR circuit) 91 that logically sums the output signals output from the shapers 11a, 11b, and 11c, and the filter output signals of the BPFs 7a, 7b, and 7c and the LPFs 10a, 10b, and 10c By a plurality of analog switches (connecting / disconnecting means) 16a, 16b, 16c and LPFs 10a, 10b, 10c Configured to include a preamble detector (preamble detection means) 17 for detecting the preamble from the output output signal. The antenna 9b is not shown.
The preamble is data of a predetermined pattern added to the head of the frame, and the preamble detector 17 detects this pattern. The preamble detector 17 determines the signal line in which the preamble data is detected from the frames that have passed through the BPFs 7a, 7b, and 7c, and turns off the analog switch 16 in the subsequent stage other than the BPF that has passed through. In this way, even if data due to noise or the like is received via another BPF in the middle of the data after the preamble, noise data is not notified to the MPU 1 as shown in FIG. Noise immunity can be increased compared to the method. In the case of simple processing, the preamble detector 17 may detect the number of times of data “1”.
As described above, according to the sixth embodiment, the analog switches 16a to 16c that connect and disconnect between the BPFs 7a to 7c and the LPFs 10a to 10c are provided, and each of the BPFs 7a to 7c is determined in order to determine which circuit is connected. Since only the signal line from which the correct preamble is detected is connected so as to detect whether the preamble included in the passed signal is correct, the correct data from which the noise component has been removed is output from the OR circuit 91. And the processing time of the MPU 1 can be shortened.

  FIG. 11 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the seventh embodiment of the present invention. The transmitter 13 according to the present invention includes an oscillator 2 that oscillates a fundamental frequency, a programmable counter (first oscillating means) 15 that can arbitrarily set a division ratio of an oscillation output signal oscillated by the oscillator 2, and a programmable counter. A frequency divider (second oscillating means) 3 that further divides the oscillation output signal divided by 15 and an AND circuit that synthesizes each oscillation output signal output by the programmable counter 15 and the frequency divider 3 ( (Combining circuit) 4 and a modulator 5 that modulates the oscillation output signal of the AND circuit 4 with the transmission data 20.

In addition, the reception device 14 has a BPF (first band pass filter) 7a that passes the first frequency band (23 MHz to 70 MHz) included in the signal received from the transmission device included in the other communication device, and other communication. BPF (second band pass filter) 7b that passes the second frequency band (5.8 MHz to 18 MHz) included in the signal received from the transmission device included in the device, and the frequency of the filter output signal that has passed BPF 7a and 7b LPFs 10a and 10b that pass low-frequency components from the components, and waveform shapers 11a and 11b that shape the filter output signals of the LPFs 10a and 10b into logic signals. The antennas 9a and 9b are not shown.
This communication device includes a transmission device 13 and a reception device 14. The transmission device 13 changes the frequency of the carrier wave using the programmable counter 15, and also divides the frequency output from the programmable counter 15 by the frequency divider 3. The carrier wave is generated by ANDing them and data is modulated using this carrier wave.
For example, the transmitter 13 divides the oscillation frequency of the oscillator 2 by using the programmable counter 15 to divide the frequency by 70, divide by 2, divide by 3, and so on. A carrier wave is a logical product of the divided rectangular wave and a waveform obtained by dividing the rectangular wave (for example, divided by 4).
This carrier wave is data-modulated by the modulator 5. The modulator 5 is configured by a circuit that performs a logical product of a carrier wave and data from the MPU 1. When the data from the MPU 1 is “0”, there is no carrier wave, and when the data is “1”, the carrier wave exists.

  The receiver 14 is connected to the BPF 7a in the carrier frequency range set by the programmable counter 15, the BPF 7b in the frequency range divided by four, and the LPFs 10a and 10b, respectively. In this way, the frequency generated by the programmable counter 15 and the frequency generated by the frequency divider 3 are separated and received simultaneously. As a result, it is possible to obtain a communication system with high noise resistance and fading resistance.

  As described above, according to the seventh embodiment, the transmission device 13 includes the programmable counter 15 that divides the oscillation output signal of the fundamental frequency by a predetermined division ratio, and further divides the signal by the predetermined division ratio. The output signal of the frequency divider 3 is combined, and the combined oscillation output signal is modulated by the transmission data 20 and transmitted. In addition, the receiving device 14 individually passes the frequency band (23 MHz to 70 MHz) of the BPF 7a and the frequency band (5, 8 MHz to 18 MHz) of the BPF 7b from the signal received from the transmitting device included in the other communication device, and these signals are transmitted. Convert to logic signal. Since these two types of logic signals are input to the MPU 1 and logically processed by software to obtain received data, communication can be performed at the best frequency. The logic signal may be logically processed by general-purpose hardware.

  FIG. 12 is a sequence diagram illustrating a case where communication is performed between terminal A and terminal B using the communication apparatus of FIG. First, terminal A transmits a frame at a frequency composed of f1 and f4, and if a response confirmation frame (ACK) from terminal B does not arrive within a certain time, it is considered that terminal B has not been reached, The value of the portion describing the programmable counter value in the header is changed to, for example, “0xF2” (“0xF1” when transmitting by f1 and f4), and transmitted at a frequency composed of f2 and f5. If the response confirmation frame (ACK) from terminal B does not arrive within a certain period of time, similarly, the value of the location describing the programmable counter value in the header in the frame is changed to, for example, “0xF3”. , F3 and f5. In this way, when communication with the corresponding terminal is not possible, the frequency is switched using the programmable counter 15 and transmitted.

  Terminal B refers to the programmable counter value in the header portion of the received frame, sets the setting value of programmable counter 15 to this counter value, and transmits a response confirmation frame. Thereby, since communication can be performed using a plurality of frequencies, a communication system that is resistant to noise and fading can be obtained.

  As described above, according to this embodiment, the communication device on the transmission side starts transmission from the higher frequency, checks whether a response signal for the frequency is returned from the reception side within a predetermined time, If not returned, the frequency dividing ratio of the oscillating means is switched to lower the frequency. This is repeated sequentially, and when the response signal is returned from the receiving side within a predetermined time, the frequency dividing ratio of the oscillating means is determined so as to be the frequency on the transmitting side at that time. The frequency dividing ratio of the oscillating means can be determined so that the oscillation output signal output from the oscillating means immediately before receiving the response signal returned from the apparatus, and communication can be performed at the best frequency.

FIG. 13 is a block diagram showing a configuration of a communication apparatus including a transmission apparatus and a reception apparatus according to the eighth embodiment of the present invention. The transmission device 13 of the present invention includes an oscillator 2 that oscillates at a fundamental frequency (70 MHz), a programmable counter (first oscillation means) 15 that can arbitrarily set a division ratio of an oscillation output signal oscillated by the oscillator 2, and A frequency divider (second oscillating means) 3 that divides the oscillation output signal oscillated by the oscillator 2 and an AND circuit that synthesizes the oscillation output signals output by the programmable counter 15 and the frequency divider 3 ( (Combining circuit) 4 and a modulator 5 that modulates the oscillation output signal of the AND circuit 4 with the transmission data 20.
In addition, the reception device 14 increases or decreases the second frequency band (2.2 MHz) around the first frequency band (70 MHz) and (35 MHz) included in the signal received from the transmission device included in another communication device. Frequency difference between BPF 7a and BPF 7b passing through frequency bands (70 MHz ± 2.2 MHz) and (35 MHz ± 2.2 MHz), and an oscillation output signal divided by programmable counter 15 and a filter output signal passing through BPF 7a and BPF 7b LPORs 10a, 10b, 10c, 10d that pass low-frequency components from the frequency components of the filter output signals that have passed through the BPFs 7a, 7b, EXOR circuits (difference detection means) 18, 19, The filter output signals of the LPFs 10a, 10b, 10c, and 10d are shaped into logic signals. And waveform shapers 11a, 11b, 11c, and 11d. The antennas 9a and 9b are not shown.
This communication device includes a transmission device 13 and a reception device 14. The transmission device 13 changes the frequency of the carrier wave using the programmable counter 15, and divides the rectangular wave output from the oscillator 2 by the frequency divider 3. Then, they are ANDed to generate a carrier wave, and this carrier wave is modulated with the transmission data 20 from the MPU 1.
If the frequency of the oscillator 2 is 70 MHz and the programmable counter 15 divides the frequency by 2, the output of the programmable counter is 35 MHz. If the frequency divider 70 divides 70 MHz of the oscillator 2 by 32, the frequency is 2.2 MHz. It becomes. If these are logically AND, the carrier wave frequencies of 35 MHz, 35 MHz ± 2.2 MHz, and 2.2 MHz are output, and the carrier wave has four frequency components. Data modulation is performed by the modulator 5 using this carrier wave.

The receiver 14 has BPF 7a, BPF 7b, EXOR circuits 18, 19 and LPFs 10a, 10b, LPFs 10a, 10b having a range of the center frequency of the waveform output from the frequency divider 3 with the waveform output from the programmable counter 15 as the center frequency. The LPFs 10a, 10b, 10c, and 10d generate and receive envelopes that pass through the BPF 7a and BPF 7b. At the same time, the frequency of the difference between the carrier waves is detected from the signals via the EXOR circuits 18 and 19, and this is input to the LPFs 10a, 10b, 10c, and 10d, whereby the frequency 2. A 2 MHz signal can be detected.
By doing so, in FIG. 12, the frequency interval between f1 and f4, the frequency interval between f2 and f5, and the frequency interval between f3 and f6 are always constant, so that it is not a signal due to noise but a regular received signal. I can confirm that. As a result, it is possible to obtain a communication system with high noise resistance and fading resistance.
As described above, according to the eighth embodiment, the transmitter 13 divides the oscillation output signal of the fundamental frequency by the programmable counter 15 that divides the oscillation output signal by the value set from the outside, and the oscillation output signal of the fundamental frequency. The output signal of the frequency divider 3 divided by a predetermined frequency dividing ratio is combined, and the combined oscillation output signal is modulated by the transmission data 20 and transmitted. Further, the receiving device 14 passes the frequency band (70 MHz, 35 MHz) of the programmable counter 15 and the frequency band (2.2 MHz) of the oscillation output signal of the frequency divider 3 from the signal received from the transmitting device included in the other communication device. The output signal from which the difference between the signal and the oscillation output signal of the programmable counter 15 is detected and the oscillation output signal of the programmable counter 15 are converted into logic signals. Since these two types of logic signals are input to the MPU 1 and logically processed by software to obtain received data, the bandwidth of the bandpass filter can be reduced with a frequency as the center. The logic signal may be logically processed by general-purpose hardware.
In addition, since the difference detection means is constituted by an exclusive OR circuit, it is possible to reliably detect the difference between the two types of frequencies with a simple circuit configuration.
In addition, the synthesis circuit used in each of the above-described embodiments includes a logical product circuit that logically ANDs the oscillation output signals output from the first oscillation unit and the second oscillation unit. With a simple circuit configuration, it is possible to reliably synthesize two types of frequencies.
The conversion circuit includes a low-pass filter that passes a low-frequency component from a frequency component of the filter output signal that has passed through the band-pass filter, and a waveform shaping unit that shapes the filter output signal of the low-pass filter into a logic signal; Therefore, a signal having a correct logic level can be obtained.
Further, since the first oscillating means and the oscillating means are constituted by a programmable counter, an arbitrary frequency dividing ratio can be set from the outside.

It is a figure which shows the structure of the communication system of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 1st Embodiment of this invention. It is a figure showing the transmission waveform on the time-axis concerning the 1st Embodiment of this invention. It is a figure of the frequency spectrum at the time of observing the transmission waveform of FIG. 3 on a frequency axis. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 3rd Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 4th Embodiment of this invention. It is a sequence diagram explaining the case where it communicates with the terminal A and the terminal B using the communication apparatus which concerns on the 4th Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the receiver which concerns on the 5th Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the receiver which concerns on the 6th Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 7th Embodiment of this invention. It is a sequence diagram explaining the case where it communicates with the terminal A and the terminal B using the communication apparatus which concerns on the 7th Embodiment of this invention. It is a block diagram which shows the structure of the communication apparatus provided with the transmitter and receiver which concern on the 8th Embodiment of this invention.

Explanation of symbols

1 MPU, 2 oscillator, 3 frequency divider, 4 AND circuit, 5 modulator, 6a, 6b antenna, 7, 8 band pass filter, 9, 10 low pass filter, 11, 12 waveform shaper, 13 transmitting device, 14 receiving device , 20 Transmission data, 22, 23, 24 Oscillation output signal

Claims (10)

A communication device that includes a transmission device and a reception device and multiplexes and communicates a plurality of different frequencies,
The transmission device includes a first oscillating unit that oscillates a fundamental frequency, a second oscillating unit that divides an oscillation output signal oscillated by the first oscillating unit by a predetermined dividing ratio, and the first oscillating unit. A synthesis circuit that synthesizes the oscillation output signals output by the oscillation means and the second oscillation means, and a modulator that modulates the oscillation output signal of the synthesis circuit with transmission data,
The receiving device converts a band-pass filter that passes a predetermined frequency band included in a signal received from the transmitting device included in another communication device, and a filter output signal that has passed the band-pass filter into a logic signal. A conversion circuit,
Received data is obtained by processing an output signal output from the conversion circuit. A communication device that includes a transmission device and a reception device and multiplexes and communicates a plurality of different frequencies,
The transmission device includes a first oscillating unit that oscillates a fundamental frequency, a second oscillating unit that divides an oscillation output signal oscillated by the first oscillating unit by a predetermined dividing ratio, and the first oscillating unit. A synthesis circuit that synthesizes the oscillation output signals output from the oscillation means and the second oscillation means, and a modulator that modulates the oscillation output signal of the synthesis circuit with transmission data,
The reception device receives a first band-pass filter that passes a first frequency band included in a signal received from the transmission device included in another communication device, and the transmission device included in the other communication device. A second band-pass filter that passes a second frequency band included in the received signal, and a plurality of conversion circuits that convert each filter output signal that has passed through each of the band-pass filters into a logic signal,
Received data is obtained by processing an output signal output from each of the conversion circuits. A communication device that includes a transmission device and a reception device and multiplexes and communicates a plurality of different frequencies,
The transmission device includes a first oscillating unit that oscillates a fundamental frequency, a second oscillating unit that divides an oscillation output signal oscillated by the first oscillating unit by a predetermined dividing ratio, and the first oscillating unit. A synthesis circuit that synthesizes the oscillation output signals output from the oscillation means and the second oscillation means, and a modulator that modulates the oscillation output signal of the synthesis circuit with transmission data,
The reception device receives a first band-pass filter that passes a first frequency band included in a signal received from the transmission device included in another communication device, and the transmission device included in the other communication device. A second band-pass filter that passes a second frequency band included in the signal, a plurality of conversion circuits that convert each filter output signal that has passed through each of the band-pass filters into a logic signal, and each of the conversion circuits A logical product circuit that performs a logical product of the output signals output from the output circuit, and a logical sum circuit that performs a logical OR operation on the output signals output from the respective conversion circuits.
A communication apparatus characterized in that received data is obtained by processing output signals output from each of the conversion circuits, the logical product circuit, and the logical sum circuit. A communication device that includes a transmission device and a reception device and performs communication by multiplexing a plurality of frequencies,
The transmission device includes an oscillator that oscillates at a fundamental frequency, a first oscillation unit that can arbitrarily set a division ratio of an oscillation output signal that is oscillated by the oscillator, and a frequency that is divided by the first oscillation unit. A second oscillation means for further dividing the oscillation output signal; a synthesis circuit for synthesizing the oscillation output signals output by the first oscillation means and the second oscillation means; and an oscillation output of the synthesis circuit. A modulator that modulates a signal with transmission data,
The receiving device includes: a first band pass filter that passes a first frequency band included in a signal received from the transmitting device included in another communication device; and the transmitting device included in the other communication device. A second band-pass filter that passes a second frequency band included in the received signal, and a conversion circuit that converts each filter output signal that has passed through each of the band-pass filters into a logic signal,
The transmission data is transmitted by setting the frequency division ratio of the first oscillating means at the time of transmission, and the reception data is obtained by processing the output signals output by the respective conversion circuits at the time of reception. Communication device. A communication device that includes a transmission device and a reception device and performs communication by multiplexing a plurality of frequencies,
The transmitter includes an oscillator that oscillates at a fundamental frequency, first oscillation means that can arbitrarily set a division ratio of an oscillation output signal oscillated by the oscillator, and an oscillation output signal that is oscillated by the oscillator. A second oscillation means that circulates, a synthesis circuit that synthesizes the oscillation output signals output by the first oscillation means and the second oscillation means, and the oscillation output signal of the synthesis circuit is modulated by transmission data And a modulator to
The receiving device has at least one or more bands that pass a frequency band obtained by increasing or decreasing a second frequency band around a first frequency band included in a signal received from the transmitting device included in another communication device. A pass filter, difference detection means for detecting a frequency difference between the oscillation output signal divided by the first oscillating means and the filter output signal passed through the band pass filter, the output of the difference detection means and the band A plurality of conversion circuits for converting the filter output signal that has passed through the pass filter into a logic signal;
A transmission apparatus that sets a frequency division ratio of the first oscillating means during transmission and transmits the transmission data, and receives data by processing output signals of the conversion circuits during reception . The communication apparatus according to claim 5 , wherein the difference detection unit is configured by an exclusive OR circuit. The combining circuit of claim 1 to 5, characterized in that it is constituted by the first oscillating means and an AND circuit for ANDing the oscillation output signal of each output by said second oscillator means The communication apparatus as described in any one. The conversion circuit includes a low-pass filter that passes a low-frequency component from a frequency component of the filter output signal that has passed through the band-pass filter, and a waveform shaping unit that shapes the filter output signal of the low-pass filter into a logic signal; the communication apparatus according to any one of claims 1 to 7, characterized in that it is configured with a. It said first oscillating means and the oscillating means, the communication apparatus according to claim 4 or 5, characterized in that it is constituted by a programmable counter. A communication method in which data is transmitted from one communication device according to any one of claims 1 to 7 and the other communication device receives the data,
The one communication device transmits the data by changing the frequency division ratio of the first oscillating means so that the frequency is sequentially lowered, and the response signal from the other communication device is not recognized within a predetermined time. If the response signal from the other communication device is recognized within a predetermined time, the frequency dividing ratio of the first oscillating means at that time is changed thereafter. A communication method characterized by performing communication.

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