Communication device, communication method, and program

Abstract

To provide a communication device, a communication method, and a program that enable suitable communication.SOLUTION: Frequency hopping is performed using a set hopping pattern so that the interval between periods in which symbols are transmitted through the same frequency channel is equal to or longer than a specific time in a plurality of frequency channels. Further, frequency hopping is performed using the set hopping pattern such that the frequency interval in one or more times of frequency hopping is equal to or greater than a specific frequency.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a communication device, a communication method, and a program. [Background technology]

[0002] As a technology for communicating using an audio signal, there has been proposed a technology for outputting an audio signal generated in response to transmission data, and acquiring reception data from an input audio signal (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-102853 A Summary of the Invention [Problem to be solved by the invention]

[0004] While the technology described in Patent Document 1 is applicable to various communications, there is a risk of problems such as difficulty in ensuring communication speed due to the operating state of the communication device and the surrounding environment.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a communication device, a communication method, and a program that enable suitable communication. [Means for solving the problem]

[0006] (1) In order to achieve the above object, a communication device according to a first aspect of the present invention comprises: A communication device that communicates using a plurality of frequency channels by frequency hopping, In the plurality of frequency channels, When the frequency channel to be used is repeatedly determined by a numerical value generated by the numerical value generating unit, The interval between periods during which symbols are transmitted on the same frequency channel is a specific time. If less than this, a redetermining is made. Thus, frequency hopping is performed using the set hopping pattern. It is characterized by:

[0008] ( 2 ) Also, the above ( 1 ) in a communication device, if a correlation function calculated using the sequence values ​​of the determined hopping pattern does not satisfy a predetermined criterion, the hopping pattern is determined again. This may be done. ( 3 ) Also, the above ( 1 ) in a communication device, Perform frequency hopping of the audio signal; This may be done.

[0009] ( 4 ) The first aspect of this invention 2 The communication method according to the aspect of A communication method for communicating using a plurality of frequency channels by frequency hopping, comprising: frequency hopping is performed using a hopping pattern set so that, when a frequency channel to be used is repeatedly determined by a numerical value generated by a numerical value generating unit, if an interval between periods during which symbols are transmitted by the same frequency channel is less than a specific time, the frequency channel to be used is redetermined; It is characterized by:

[0011] ( 5 ) Also, the above ( 4 ) communication method, if a correlation function calculated using the sequence values ​​of the determined hopping pattern does not satisfy a predetermined criterion, the hopping pattern is determined again. This may be done. ( 6 ) Also, the above ( 4 ) communication method, Perform frequency hopping of the audio signal; This may be done.

[0012] ( 7 ) The first aspect of this invention 3 The program related to the above points is as follows: Computer, functioning as a signal processing means for communicating using a plurality of frequency channels by frequency hopping; the signal processing means performs frequency hopping using a hopping pattern set so that, when a frequency channel to be used is repeatedly determined by a numerical value generated by a numerical value generating unit, if an interval between periods during which symbols are transmitted by the same frequency channel is less than a specific time, the signal processing means performs frequency hopping using a hopping pattern set so as to perform redetermining the frequency channel to be used among the plurality of frequency channels. It is characterized by:

[0014] ( 8 ) Also, the above ( 7 ) program, the signal processing means re-determines the hopping pattern when a correlation function calculated using the sequence value of the determined hopping pattern does not satisfy a predetermined criterion. This may be done. ( 9 ) Also, the above ( 7 ) program, The signal processing means performs frequency hopping of the audio signal. This may be done. Effect of the Invention

[0015] According to the present invention, favorable communication is possible. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 illustrates an example of the configuration of a communication device. [Diagram 2] FIG. 2 is a diagram illustrating an example of the configuration of a transmitter. [Diagram 3] FIG. 2 illustrates an example frequency hopping signal. [Figure 4] 13 is a flowchart illustrating an example of a hopping pattern creation process. [Diagram 5] FIG. 13 is a diagram illustrating an example of determining a hopping pattern. [Figure 6]FIG. 1 is a diagram illustrating an example of a configuration of a communication system to which a communication device is applied. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] A communication device according to an embodiment of the present invention will be described below. The communication device of the present invention may be configured as a mobile communication terminal that can be carried by a user, or may be configured as a fixed communication terminal that is fixed to a specific installation location. The mobile communication terminal may be, for example, a mobile phone, a smartphone, a tablet terminal, or the like. The communication device is capable of communicating with other mobile communication terminals or fixed communication terminals by transmitting and receiving voice signals. Note that the communication device is not limited to one that transmits and receives voice signals, and may be, for example, one that only transmits voice signals and does not receive voice signals.

[0018] FIG. 1 shows an example of the configuration of a communication device 100 according to an embodiment of the present invention. The communication device 100 includes an audio processing unit 110, a storage unit 120, a control unit 130, an input / output unit 140, and a communication processing unit 150. A microphone 111 and a speaker 112 are connected to the audio processing unit 110. The microphone 111 and the speaker 112 may be built into the communication device 100 or may be externally attached to the communication device 100. When the communication device 100 only transmits audio signals, the speaker 112 may be connected to the audio processing unit 110, while the microphone 111 may not be provided. The units of the communication device 100 are connected to each other via an internal bus so that electrical signals can be transmitted between them.

[0019] The audio processing unit 110 is configured using, for example, a digital signal processor (DSP), a digital-to-analog converter (DAC), and an analog-to-digital converter (ADC), and executes signal processing for transmitting and receiving an audio signal in cooperation with the control unit 130. The signal processing by the audio processing unit 110 includes processing for outputting an audio signal from the speaker 112 based on transmission data, and processing for acquiring reception data based on an audio signal input to the microphone 111. The audio signal is used as a carrier wave for transmitting various data. The audio processing unit 110 outputs an audio signal by converting a digital signal corresponding to the transmission data into an analog signal and supplying the analog signal to the speaker 112. The audio processing unit 110 also converts an analog signal corresponding to the audio signal input to the microphone 111 into a digital signal to acquire reception data.

[0020] The storage unit 120 includes, for example, a random access memory (RAM), a read only memory (ROM), a flash memory, etc., and stores various information, fixed data, applications, screen data, a terminal ID, and programs for the control unit 130 to execute various processes. The programs executed by the control unit 130 include a transmission program 121 and a reception program 122. The control unit 130 executes the transmission program 121, causing the communication device 100 to function as a transmitter. The control unit 130 executes the reception program 122, causing the communication device 100 to function as a receiver. The transmission program 121 and the reception program 122 may be prepared as separate programs or as a single program.

[0021] The control unit 130 includes, for example, a microprocessor such as a CPU (Central Processing Unit), and executes a program stored in the storage unit 120 to perform control related to communication using audio signals. The control unit 130 may control the communication device 100 to switch between either a transmitter or a receiver by executing either a transmission program 121 or a reception program 122. Alternatively, the control unit 130 may control the communication device 100 to function as both a transmitter and a receiver by executing the transmission program 121 and the reception program 122 in parallel.

[0022] The input / output unit 140 includes a keypad, a liquid crystal display, a light emitting diode, etc., and provides an interface for inputting or outputting various information. Note that the communication device 100 may be configured without a part or all of the input / output unit 140. The microphone 111 and the speaker 112 may constitute a part of the input / output unit 140.

[0023] The communication processing unit 150 includes, for example, an antenna, an RF (Radio Frequency) signal processing circuit, a baseband signal processing circuit, etc., and executes processing for communicating with an external device via part or all of a mobile communication network, a short-range wireless communication network, a wired communication network, the Internet, or any other telecommunication network.

[0024] The communication device 100 communicates using a plurality of frequency channels for audio signals by switching among the plurality of frequency channels by a frequency hopping (FH) method and transmitting symbols. The communication device 100 uses, for example, an audio signal in an inaudible band as a carrier wave. In this way, if communication is performed using an audio signal in an inaudible band, it becomes impossible or difficult for humans to hear the signal, so that the user of the communication device 100 does not feel noise and discomfort can be prevented.

[0025] In the communication device 100, the control unit 130 executes the transmission program 121 and cooperates with the audio processing unit 110 to function as a transmitter 500. In this manner, the transmitter 500 is realized by the execution of the transmission program 121 by the control unit 130, and has various functional configurations.

[0026] 2 shows a configuration example of a transmitter 500. The transmitter 500 includes a primary modulation section 501, a serial-parallel conversion section 502, a hopping pattern generation section 503, a hopping frequency generation section 504, a frequency conversion section 505, a window processing section 506, and a parallel-serial conversion section 507. These functional configurations are constructed by software and hardware resources working together, and it is sufficient that information processing by software is realized using the hardware resources.

[0027] The primary modulation unit 501 performs modulation according to the bit value of the transmission data, for example, by narrowband modulation such as Frequency Shift Keying (FSK). In this case, the transmission data is divided into a predetermined size, for example, 1 bit, and the frequency of the modulated signal is shifted for each symbol section to which each divided data is assigned. Note that the method is not limited to dividing the transmission data into 1 bit units, and may be MFSK (M-ary FSK) in which multiple bits of the transmission data are collected and converted into symbols, using multiple frequencies. However, in communication using voice signals, it is difficult to use MFKS because the available band is limited. The transmission data may be data read from the storage unit 120, or may be data created by processing in the control unit 130.

[0028] The serial-parallel conversion unit 502 receives the modulated signal from the primary modulation unit 501 and converts the input signal from a serial signaling system to a parallel signaling system. At this time, the serial signaling system input signal corresponding to a symbol sequence in which a plurality of symbols are consecutive is output in a parallel signaling system as a signal in a symbol interval divided into unit intervals. This output signal may be a signal having a frequency corresponding to the symbol value transmitted in each symbol interval for each of a plurality of frequency channels. Therefore, the serial-parallel conversion unit 502 outputs a signal obtained by dividing the symbol sequence into unit intervals. The signal converted to the parallel signaling system by the serial-parallel conversion unit 502 is supplied to a frequency conversion unit 505.

[0029] The hopping pattern generating unit 503 generates a preset hopping pattern. A hopping control signal corresponding to the generated hopping pattern is supplied to the hopping frequency generating unit 504. The hopping control signal may be a signal that controls switching of the output frequency of the hopping frequency generating unit 504 in accordance with the preset hopping pattern. The hopping frequency generating unit 504 switches, for example, the frequency of a tone signal in response to the hopping control signal from the hopping pattern generating unit 503, and supplies the switched frequency to the frequency converting unit 505.

[0030] The frequency conversion unit 505 converts the signal supplied from the serial-parallel conversion unit 502 into a signal of an audio frequency band corresponding to the plurality of frequency channels. For example, the signal supplied from the serial-parallel conversion unit 502 may be multiplied by the signal supplied from the hopping frequency generation unit 504. As a result, a plurality of channel signals in which symbols are assigned to a plurality of frequency channels corresponding to a plurality of symbol periods for transmitting a plurality of symbols, respectively, are generated. Each channel signal may be a signal that forms a localized wave in the symbol period. Therefore, the frequency conversion unit 505 generates a plurality of channel signals in which a signal obtained by dividing the symbol sequence by the serial-parallel conversion unit 502 for each unit interval is assigned to a plurality of frequency channels used for frequency hopping. The channel signal output from the frequency conversion unit 505 is input to the window processing unit 506. The window processing unit 506 functions as a band pass filter to remove unnecessary frequency components. This prevents the occurrence of inter-symbol interference. After that, each channel signal is input to the parallel-serial conversion unit 507.

[0031] The parallel-serial converter 507 receives the output signal from the window processor 506 and supplies the input signal to an adder, thereby converting from the parallel signaling system to the serial signaling system. At this time, in the multiple frequency channels, a symbol period in which a symbol is transmitted by one frequency channel is started at an interval shorter than the symbol period in which a symbol is transmitted by another frequency channel. In this way, when serialization is performed to convert from the parallel signaling system to the serial signaling system, the interval between the symbols assigned to the multiple frequency channels is made shorter than the symbol period required to transmit a symbol in each frequency channel. Then, a part of the symbol period in which transmission started earlier becomes the same period as a part of the symbol period in which transmission started later, thereby performing frequency hopping while overlapping the symbols.

[0032] For example, in the case of FSK, which converts 1-bit data into symbols, with conventional frequency hopping, if the symbol length is Ts, the maximum communication speed is 1 / Ts [bps]. However, by narrowing the interval between symbols assigned to multiple frequency channels to be shorter than the symbol period required to transmit a symbol on each frequency channel, the communication speed can be made faster than 1 / Ts [bps].

[0033] The signal converted into the serial signal format by the parallel-serial converter 507 may be supplied as an audio output signal to the DAC of the audio processor 110 and converted into an analog signal. The audio output signal thus converted into an analog signal is supplied to the speaker 112 and output as an audio signal.

[0034] FIG. 3 illustrates frequency hopping signals with and without channel multiplexing, which is a process of overlapping symbols assigned to multiple frequency channels. Here, a case is shown in which the hopping rate is the same as the symbol rate among FFH (Fast-FH) in which the hopping rate is equal to or higher than the symbol rate. In addition, eight frequency channels Ch0 to Ch7 are used as the multiple frequency channels. Note that SFH (Slow-FH) in which the hopping rate is lower than the symbol rate may be used. FFH in which the hopping rate is higher than the symbol rate may be used. In this embodiment, the channel multiplexing does not necessarily overlap the entire period in which symbols are transmitted in the multiple frequency channels, but may be such that a part (the latter half) of a period in which symbol transmission is started first in a first channel included in the multiple frequency channels overlaps a part (the former half) of a period in which symbol transmission is started later in a second channel included in the multiple frequency channels.

[0035] Fig. 3(a) shows a case without channel multiplexing, in which a symbol period for transmitting symbols by one frequency channel included in the plurality of frequency channels is started at the same interval as a symbol period for transmitting symbols by another frequency channel included in the plurality of frequency channels. For example, in the case shown in Fig. 3(a), in the symbol transmission period from timing T0 to timing T1, symbol transmission is performed by frequency channel Ch0, and symbol transmission is not performed by other frequency channels. At timing T1, frequency hopping is performed to switch the frequency used for symbol transmission. As a result, in the symbol transmission period from timing T1 to timing T2, symbol transmission is performed by frequency channel Ch2, and symbol transmission is not performed by other frequency channels.

[0036] FIG. 3(b) shows a case where channel multiplexing is used, and the interval between symbols assigned to multiple frequency channels is shortened to time Ts / 3, which is 1 / 3 of the symbol length Ts. That is, a symbol period for transmitting a symbol is started by another frequency channel included in the multiple frequency channels at time Ts / 3, which is a shorter interval than the symbol period for transmitting a symbol by one frequency channel included in the multiple frequency channels. Note that, until the symbol period set corresponding to one frequency channel ends, the transmission of symbols by the first frequency channel that started earlier continues even if a symbol period for transmitting a symbol by another frequency channel starts. Therefore, a part of the symbol period in one frequency channel becomes the same period as a part of the symbol period in another frequency channel, and frequency hopping is performed while overlapping the symbols.

[0037] In the case shown in FIG. 3(b), the period from timing T0 to timing T1 is a symbol period during which symbols are transmitted by frequency channel Ch0, similar to the case shown in FIG. 3(a). In contrast, in the case shown in FIG. 3(b), unlike the case shown in FIG. 3(a), symbol transmission by other frequency channels is started between timing T0 and timing T1. For example, symbol transmission by frequency channel Ch2 is started at timing T01, which is a time Ts / 3 after timing T0. Furthermore, symbol transmission by frequency channel Ch6 is started at timing T02, which is a time Ts / 3 after timing T01. Symbol transmission by frequency channel Ch2, which is started at timing T01, continues until timing T11. Symbol transmission by frequency channel Ch6, which is started at timing T02, continues until timing T12.

[0038] 3(b) is defined as a first period from timing T0 to timing T1, and a second period from timing T01 to timing T11, a second period in which symbols are transmitted using another frequency channel Ch2 included in the multiple frequency channels is started at an interval shorter than the first period in which symbols are transmitted using one frequency channel Ch0 included in the multiple frequency channels. Also, the period from timing T01 to timing T1 included in part of the first period from timing T0 to timing T1 overlaps with and is the same period as the period from timing T01 to timing T1 included in part of the second period from timing T01 to timing T11.

[0039] 3(b) is defined as a first period from timing T01 to timing T11, and a second period from timing T02 to timing T12, a second period in which symbols are transmitted using another frequency channel Ch6 included in the multiple frequency channels is started at an interval shorter than the first period in which symbols are transmitted using one frequency channel Ch2 included in the multiple frequency channels. Also, the period from timing T02 to timing T11 included in the first period from timing T01 to timing T11 overlaps with the period from timing T02 to timing T11 included in the second period from timing T02 to timing T12, becoming the same period.

[0040] In the period from timing T02 to timing T1 shown in FIG. 3(b), three symbols are multiplexed and transmitted on frequency channels Ch0, Ch2, and Ch6. In each of the following periods, three symbols are multiplexed and transmitted in the same manner. In this way, when the symbol interval is shortened to a time Ts / 3, which is 1 / 3 of the symbol length Ts, and transmitted, the communication speed can be increased to 3 / Ts, which is three times faster than the case without channel multiplexing. The shortening amount of the symbol interval may be determined in advance as a communication specification, and may be less than 1 / 3, such as 1 / 2, or may be more than 1 / 3, such as 1 / 4. In any case, the communication speed can be increased by shortening the symbol interval and transmitting it. In the example shown in FIG. 3, the hopping rate is the same as the symbol rate, so one symbol is multiplexed with other symbols and transmitted. On the other hand, in the case of FFH where the hopping rate is higher than the symbol rate, channel multiplexing may be performed so that localized waves corresponding to multiple chips transmitting one symbol overlap. For example, in the case shown in FIG. 3(a), one symbol may be transmitted using a symbol transmission period from timing T0 to timing T1 and a symbol transmission period from timing T1 to timing T2. In this case, in the first period from timing T0 to timing T1 shown in FIG. 3(b), one symbol is transmitted in common with the second period from timing T01 to timing T11. Then, the period from timing T01 to timing T1 included in part of the first period from timing T0 to timing T1 overlaps with the period from timing T01 to timing T1 included in part of the second period from timing T01 to timing T11, becoming the same period. In this case as well, the interval between symbols can be shortened for transmission, and further, the communication speed can be increased by shortening the interval between chips transmitting one symbol for transmission.

[0041] However, since the audio signal is transmitted by vibration of air, it is easily affected by the operating state of the communication device 100 and the surrounding environment. Therefore, if the interval between symbols is too short, a problem occurs in that symbols transmitted on the same frequency channel are easily affected by interference due to a multipath environment. In addition, when frequency hopping is performed while overlapping symbols, a problem occurs in that if the frequency interval is too narrow, the symbols are easily affected by interference due to Doppler shift, as a result of a part of a symbol period in which transmission starts earlier becoming the same period as a part of a symbol period in which transmission starts later. In order to solve these problems, a pattern that satisfies a predetermined condition is set in advance as a hopping pattern generated by the hopping pattern generating unit 503.

[0042] 4 is a flowchart showing an example of a hopping pattern creation process executed to create a hopping pattern. The hopping pattern creation process may be executed according to a program read by the control unit 130 of the communication device 100 from the storage unit 120, or may be executed using a computer system different from the communication device 100. The hopping pattern created by the hopping pattern creation process is stored in the storage unit 120 of the communication device 100 and used by the hopping pattern generation unit 503. In this hopping pattern creation process, an initial value "0" is set to a variable i at first (step S101).

[0043] Next, a sequence value Pn[i] indicated by using a variable i in the hopping pattern is determined (step S102). The sequence value Pn[i] is the (i+1)th sequence value in the hopping pattern, and indicates the number of the frequency channel used for transmitting the symbol. For example, when the variable i=0, the first (initial) sequence value Pn[0] is determined to be an arbitrary value. When the variation i≧1, the sequence value Pn[i] is determined by a random number generated by a random number generator such as a PN sequence generator.

[0044] Next, it is determined whether the determined sequence value Pn[i] is the same as the sequence value Pn[ij] determined earlier (step S103). Here, variable j is an integer in the range of 1 to m, and constant m may be determined in advance as a specification of the hopping pattern. In step S103, if the sequence value Pn[i] determined this time is included among the sequence values ​​determined from one to m before the current determination, it may be determined that they are the same. If the sequence value Pn[i] is the same as the sequence value Pn[ij] (step S103; Yes), the process returns to step S102 and the sequence value Pn[i] is determined again.

[0045] If the sequence value Pn[i] is not the same as the sequence value Pn[ij] (step S103; No), the currently determined sequence value Pn[i] is compared with the previously determined sequence value Pn[i-1], and it is determined whether the difference is within the range k (step S104). The variable k indicating the range k is an integer in the range of 1 to n, and the constant n may be previously determined as a specification of the hopping pattern. The difference between the sequence value Pn[i] and the sequence value Pn[i-1] is also called the hopping distance, and corresponds to the frequency interval in the frequency channel switched by frequency hopping. In step S104, it is determined that the difference is within the range k if the difference between the currently determined sequence value Pn[i] and the previously determined sequence value Pn[i-1] is within the range of -n to n using a previously determined constant n (positive integer). If it is within this range k (step S104; Yes), the process returns to step S102 and the sequence value Pn[i] is determined again. In step S104, it may be determined whether or not not only the difference between the currently determined sequence value Pn[i-1] and the previously determined sequence value Pn[i-j'], but also the difference between the currently determined sequence value Pn[i-1] and the previously determined sequence value Pn[i-j'] is within the range k. The variable j' is an integer equal to or greater than 2, and may be determined in advance as a specification of the hopping pattern so that interference due to Doppler shift can be prevented. The process when it is within the range k and the process when it is not within the range k may be the same as the process when it is the difference from the sequence value Pn[i-1].

[0046] If the difference is not within the range k (step S104; No), it is determined whether the variable i has reached the upper limit for creation (step S105). If it is not the upper limit for creation (step S105; No), the variable i is updated by incrementing it by 1 (step S106), and the process returns to step S102 to determine the next sequence value.

[0047] If the variable i is equal to the upper limit for creation (step S105; Yes), a predetermined cyclic check is performed to determine whether a predetermined criterion is satisfied (step S107). For example, when the head and tail of the hopping patterns determined in steps S101 to S106 are connected, it is determined whether the same conditions as those in steps S103 and S104 are satisfied.

[0048] If the cyclic check result does not satisfy the condition (step S107; No), a part or all of the hopping pattern is redetermined as a cyclic redetermining (step S108). For example, the sequence value of the tail of the hopping pattern may be redetermined so as to satisfy the same conditions as in steps S103 and S104.

[0049] When the cyclic check result satisfies the condition (step S107; Yes) or after the cyclic redetermination, a predetermined quality evaluation is performed to determine whether or not a predetermined standard is satisfied (step S109). For example, when an autocorrelation function is calculated using the sequence values ​​of the determined hopping pattern, it is judged whether the S / N ratio (Signal-to-Noise Ratio) is equal to or greater than a predetermined standard value. Also, when a correlation function between the whole sequence values ​​of the determined hopping pattern and a part of it is calculated, it is judged whether the S / N ratio is equal to or greater than a predetermined standard value.

[0050] If the quality evaluation result does not satisfy the condition (step S109; No), the hopping pattern is redetermined as quality redetermination (step S110). For example, the hopping pattern may be redetermined by executing steps S101 to S108 again. Note that, among the multiple hopping patterns determined by executing steps S101 to S108 multiple times, the hopping pattern having the highest S / N ratio when the autocorrelation function is calculated may be selected. Also, among the multiple hopping patterns determined by executing steps S101 to S108 multiple times, the hopping pattern having the highest S / N ratio when the correlation function between all and part of the sequence values ​​is calculated may be selected.

[0051] In such a hopping pattern creation process, if the interval between the periods during which symbols are transmitted by the same frequency channel in a plurality of frequency channels is less than a specific time, the matching condition determined in step S103 is not satisfied, and the sequence value is re-determined. Also, if the frequency interval between the frequency channels selected by one or more frequency hoppings in a plurality of frequency channels is less than a specific frequency, the matching condition determined in step S104 is not satisfied, and the sequence value is re-determined. The hopping pattern created in this way is stored in the storage unit 120 and set in advance as a hopping pattern to be generated by the hopping pattern generation unit 503. Therefore, frequency hopping is performed using a hopping pattern set so that the interval between the periods during which symbols are transmitted by the same frequency channel in a plurality of frequency channels is equal to or greater than a specific time. Also, frequency hopping is performed using a hopping pattern set so that the frequency interval in one or more frequency hoppings is equal to or greater than a specific frequency, that is, so that the frequency interval is equal to or greater than a specific frequency when a predetermined number of frequency hoppings are performed in a plurality of frequency channels and symbols are transmitted by different frequency channels. In this way, the hopping pattern is set so that the frequency channel after the change by frequency hopping satisfies a time compatibility condition that is a predetermined time compatibility condition, that is, the interval between the use of the same frequency channel. Also, the hopping pattern is set so that the frequency channel after the change by frequency hopping satisfies a frequency compatibility condition that is a predetermined frequency compatibility condition, that is, the frequency interval between one or more frequency channels used before the change. This makes it difficult for the communication device 100 to be affected by the operating environment and surrounding environment, such as the influence of interference due to a multipath environment and the influence of interference due to Doppler shift, and improves the quality of communication using voice signals.

[0052] The hopping frequency generating unit 504 switches the output frequency according to a hopping control signal corresponding to the hopping pattern generated by the hopping pattern generating unit 503, and supplies the output frequency to the frequency converting unit 505. The frequency converting unit 505 generates a channel signal forming a localized wave in a symbol period by, for example, multiplying the signal supplied from the serial-parallel converting unit 502 by the signal supplied from the hopping frequency generating unit 504. In the channel signal corresponding to a plurality of frequency channels, adjacent localized waves in the time domain have an interval of a specific time or more, and adjacent localized waves in the frequency domain have an interval of a specific frequency or more. In this way, by generating a hopping pattern in which the localized waves are arranged so as not to overlap, mutual interference can be avoided, and the quality of communication using voice signals can be improved.

[0053] Fig. 5 shows an example of determining a hopping pattern. Here, in order to execute the hopping pattern creation process of Fig. 4, a predetermined constant m=6 and a constant n=1 are set. That is, if the same sequence value is included among the sequence values ​​determined up to the sixth previous sequence value, the process returns to step S102 and the sequence value is determined again, based on the determination result of step S103. Also, if the difference from the previously determined sequence value is ±1, the process returns to step S102 and the sequence value is determined again, based on the determination result of step S104.

[0054] 5(a) is an example of determining hopping pattern HP01, which includes sequence values ​​that do not satisfy the conditions in step S103 and sequence values ​​that do not satisfy the conditions in step S104. For example, when variable i=6 and when variable i=8, sequence value Pn[i]=6, but in step S103, when variable i=8 and variable j=2, Pn[8]=Pn[6], and it is determined that they are the same. Also, when variable i=11, sequence value Pn[i]=0, and when variable i=12, sequence value Pn[i]=1, but in step S104, when variable i=12, Pn

[12] =Pn

[11] +1, and it is determined that the difference is included in range k.

[0055] 5(b) is an example of determining hopping pattern HP02, which does not include sequence values ​​that do not satisfy the conditions of step S103 or the conditions of step S104. In hopping pattern HP02, the sequence value Pn[3]=2 when variable i=3, the sequence value Pn[4]=0 when variable i=4, the sequence value Pn[5]=4 when variable i=5, the sequence value Pn[8]=3 when variable i=8, the sequence value Pn[9]=5 when variable i=9, the sequence value Pn

[12] =2 when variable i=12, the sequence value Pn

[13] =6 when variable i=13, the sequence value Pn

[14] =4 when variable i=14, and the sequence value Pn

[15] =1 when variable i=15 have been changed from hopping pattern HP01.

[0056] In the communication device 100, the control unit 130 executes the receiving program 122 and cooperates with the audio processing unit 110 to function as a receiver. The receiver obtains received data from the received audio signal by a method reverse to the method used by the transmitter 500 to create an audio signal corresponding to the transmitted data. Alternatively, some or all of the receiving method may be modified to obtain a more reliable received data output than simply using the reverse method of the transmission method. The communication device 100 serving as a receiver is realized by the execution of the receiving program 122 by the control unit 130, and has various functional configurations.

[0057] 6 shows a configuration example of a communication system 1 to which the communication device 100 can be applied. The communication system 1 includes a user terminal 10 carried by a user and a store terminal 20 installed in a store. The above-mentioned communication device 100 is applied as the user terminal 10 and the store terminal 20, which communicate with each other by transmitting and receiving voice signals.

[0058] In the communication system 1, for example, when a user visits a store, the user terminal 10 transmits information identifying the user to the store terminal 20. In response to the information received from the user terminal 10, the store terminal 20 can return various store information and the like. The store information may include product information, service information, schedule information, point allocation information, location information, some or all of these pieces of information, and any other information related to the store.

[0059] The communication system 1 may be used as a payment system. In this case, the store terminal 20 executes various processes as a payment terminal. For example, when purchasing a product, the user terminal 10 transmits a user ID (Identifier) ​​to the store terminal 20 by communication using a voice signal in response to an operation by the user. The store terminal 20 performs payment processing using the user ID received from the user terminal 10 and the payment amount acquired in the procedure at the time of purchasing the product. In the payment processing, for example, the store terminal 20 transmits the user ID and the payment amount to a payment server connected via a telecommunications network, and receives an authentication result and a payment result from the payment server. After executing the payment processing, the store terminal 20 transmits the authentication result and the payment result to the user terminal 10 by communication using a voice signal. The user terminal 10 that receives the authentication result and the payment result notifies the user that the payment has been completed or that an error has occurred by displaying a screen, outputting a voice, or the like.

[0060] As described above, in the communication device 100, in communication using multiple frequency channels by frequency hopping of the voice signal, the second period in which symbols are transmitted using another frequency channel included in the multiple frequency channels is started at an interval shorter than the first period in which symbols are transmitted using one frequency channel included in the multiple frequency channels, and a part of the first period and a part of the second period overlap each other to become the same period. This makes it possible to increase the communication speed when using the voice signal and increase the amount of communication data.

[0061] By performing frequency hopping using the hopping pattern created by the hopping pattern creation process shown in Fig. 4, the interval between periods during which symbols are transmitted over the same frequency channel becomes equal to or longer than a specific time in multiple frequency channels. This reduces the effects of interference in a multipath environment, improves the quality of communication using voice signals, and prevents a decrease in communication speed.

[0062] By performing frequency hopping using the hopping pattern created by the hopping pattern creation process shown in Fig. 4, the frequency interval in one frequency hopping becomes a specific frequency or more. This reduces the influence of interference due to Doppler shift, improves the quality of communication using voice signals, and prevents a decrease in communication speed.

[0063] The present invention is not limited to the above-described embodiment, and various modifications and applications are possible. For example, the communication device 100 does not need to have all the technical features described in the above-described embodiment, and may enable part of the configuration, function, and operation described in the above-described embodiment so as to solve at least one problem in the conventional technology.

[0064] Signals and information can be represented using any technology, and for example, data, instructions, commands, information, signals, bits, symbols, and channels may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical electric fields or optical particles, or a combination of any or all of these. The communication device 100 and the communication method using the same described in the above embodiment may be applied to wireless communication using electromagnetic signals, not limited to communication using voice signals.

[0065] The logical blocks, modules, circuits, processing steps, and algorithms that realize the configuration, functions, and operations of the communication device 100 may be implemented as hardware such as electronic circuits, software such as computer programs, or a combination of these. For example, application software for realizing the functions of the communication device 100 described in the above embodiment may be provided, and by installing the application software in an information and communication device such as a smartphone, communication using audio signals may be possible without adding new dedicated hardware.

[0066] The logic blocks, modules, and circuits that realize the configuration, functions, and operations of communication device 100 may be implemented as a general-purpose microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device including a field programmable gate array (FPGA), other semiconductor integrated circuits, or a combination of these.

[0067] Software for implementing the configuration, functions, and operations of the communication device 100 may be stored or transmitted as one or more instructions or codes in various computer-readable media. The various computer-readable media may be storage media or communication media. The storage medium may be configured using any storage device, such as RAM, ROM, EEPROM, CD-ROM or other optical disk storage device, magnetic disk storage device, or semiconductor storage device. The communication medium may be configured using any signal transmission medium, such as wired, infrared, wireless, microwave, or ultrasonic. [Explanation of symbols]

[0068] 1. Communication Systems 10 User terminal 20 Store terminals 100 Communication equipment 110 Audio processing unit 111 Mike 112 Speaker 120 Storage section 121 Transmission Program 122 Receiving Program 130 Control section 140 Input / output section 150 Communication processing unit 500 Transmitter 501 Primary Modulation Section 502 Serial-to-parallel conversion section 503 Hopping pattern generator 504 Hopping frequency generator 505 Frequency conversion unit 506 Window Processing Unit 507 Parallel serial conversion section

Claims

1. A communication device that communicates using a plurality of frequency channels by frequency hopping, frequency hopping is performed using a hopping pattern set so that, when a frequency channel to be used is repeatedly determined by a numerical value generated by a numerical value generating unit, if an interval between periods during which symbols are transmitted by the same frequency channel is less than a specific time, the frequency channel to be used is redetermined; A communication device comprising:

2. if a correlation function calculated using the sequence values ​​of the determined hopping pattern does not satisfy a predetermined criterion, the hopping pattern is determined again.

2. The communication device according to claim 1 .

3. Perform frequency hopping of the audio signal; 2. The communication device according to claim 1 .

4. A communication method for communicating using a plurality of frequency channels by frequency hopping, comprising: frequency hopping is performed using a hopping pattern set so that, when a frequency channel to be used is repeatedly determined by a numerical value generated by a numerical value generating unit, if an interval between periods during which symbols are transmitted by the same frequency channel is less than a specific time, the frequency channel to be used is redetermined; A communication method comprising:

5. if a correlation function calculated using the sequence values ​​of the determined hopping pattern does not satisfy a predetermined criterion, the hopping pattern is determined again.

5. The communication method according to claim 4.

6. Perform frequency hopping of the audio signal; 5. The communication method according to claim 4.

7. Computer, functioning as a signal processing means for communicating using a plurality of frequency channels by frequency hopping; the signal processing means performs frequency hopping using a hopping pattern set so that, when a frequency channel to be used is repeatedly determined by a numerical value generated by a numerical value generating unit, if an interval between periods during which symbols are transmitted by the same frequency channel is less than a specific time, the signal processing means performs frequency hopping using a hopping pattern set so as to perform redetermining the frequency channel to be used among the plurality of frequency channels. A program characterized by:

8. the signal processing means re-determines the hopping pattern when a correlation function calculated using the sequence value of the determined hopping pattern does not satisfy a predetermined criterion.

8. The program according to claim 7 .

9. The signal processing means performs frequency hopping of the audio signal.

8. The program according to claim 7 .

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