Wireless communication device, wireless communication method, and communication control program

Abstract

To allow the transmission speed of a Morse signal of its own station to be automatically adjusted to match that of a partner station.SOLUTION: A transceiver (1) transmits and receives Morse signals. The transceiver (1) includes a WPM estimation unit (663) that estimates the keying speed of a partner station of a Morse signal as WPM based on the Morse signal received from the partner station, a setting unit (92) that sets a target value for the keying speed of the Morse signal of its own station based on the estimated keying speed of the partner station, and an electric keyer (93) that controls the keying speed of the own station so that it becomes the set target value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a wireless communication device that transmits and receives Morse signals and the like.

Background Art

[0002] In communication using a wireless communication device that transmits and receives Morse signals by unmodulated continuous wave (CW), there may be a difference in skill in operating an input device for inputting Morse codes combining short dots and long dots between communicators. When such a difference in skill occurs, a difference in the transmission speed of Morse signals will occur between communicators. Therefore, when an advanced user and a beginner communicate, in the wireless communication device on the advanced user side, by adjusting the transmission speed so as to match the transmission speed of the beginner's wireless communication device with a slow operation of the input device, communication can be smoothly performed. In the following description, a signal obtained by converting a Morse code combining short dots and long dots for communication is referred to as a Morse signal.

[0003] In addition, among the above-mentioned wireless communication devices, there are models equipped with a so-called electric keyer that continuously outputs short dots or long dots, or outputs short dots, long dots, and the intervals between them at a specified length according to the input. For example, Patent Document 1 discloses changing each of the minimum position and the maximum position of the variable position of a variable resistor that varies the transmission speed in an electric keyer. By changing the minimum position and the maximum position, the operation range of the knob for varying the resistance value of the variable resistor can be set according to the operation skill of the input device of the sender.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the prior art as described above has a problem that it cannot be freed from the annoyance of the knob operation because the transmission speed is adjusted by the knob operation.

[0006] One aspect of the present invention aims to automatically adjust the transmission speed of the local station of the Morse signal to match the transmission speed of the other station.

Means for Solving the Problems

[0007] In order to solve the above problems, a wireless communication device according to one aspect of the present invention is a wireless communication device that transmits and receives Morse signals, and includes an estimation unit that estimates the transmission speed of the other station of the Morse signal based on the Morse signal received from the other station, a setting unit that sets a target value of the transmission speed of the local station of the Morse signal based on the estimated transmission speed of the other station, and a control unit that controls the transmission speed of the local station to reach the set target value.

[0008] In order to solve the above problems, a wireless communication method according to one aspect of the present invention is a wireless communication method that transmits and receives Morse signals, and includes an estimation step of estimating the transmission speed of the other station of the Morse signal based on the Morse signal received from the other station, a setting step of setting a target value of the transmission speed of the local station of the Morse signal based on the estimated transmission speed of the other station, and a control step of controlling the transmission speed of the local station to reach the set target value.

Effects of the Invention

[0009] According to one aspect of the present invention, the transmission speed of the local station of the Morse signal can be automatically adjusted to match the transmission speed of the other station.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0011] 〔Embodiment〕 Hereinafter, an embodiment of the present invention will be described in detail.

[0012] 〈Outline of Transceiver〉 FIG. 1 is a block diagram showing the configuration of a transceiver 1 according to this embodiment.

[0013] As shown in FIG. 1, the transceiver 1 includes an antenna 2, a receiving unit 3, a transmitting unit 4, a transmitting / receiving switching unit 5, a CW decoding unit 6, a character display unit 7, a code input device 8, a CPU (Central Processing Unit) 9, a memory 10, and a bandpass filter 11. The transceiver 1 is a wireless communication device having a function of transmitting and receiving Morse signals.

[0014] The receiving unit 3 demodulates Morse audio based on the Morse signal received from the antenna 2. The transmitting unit 4 converts a short dot signal or a long dot signal output from an electric keyer 93 described later into a CW (Continuous Wave) signal, and further performs predetermined processing and transmits it.

[0015] The transmitting / receiving switching unit 5 switches between the connection of the bandpass filter 11 and the receiving unit 3 and the connection of the bandpass filter 11 and the transmitting unit 4. The transmitting / receiving switching unit 5 includes a semiconductor switch, a relay, and the like. The bandpass filter 11 is provided between the antenna 2 and the transmitting / receiving switching unit 5. The bandpass filter 11 passes the received signal in the receiving frequency band and excludes components in other bands. Thereby, the amplitude of the signal input to an A / D converter 33 described later can be suppressed, and overflow during A / D conversion can be prevented. Also, the bandpass filter 11 performs band limiting on the transmission signal from the transmitting unit 4.

[0016] The CW decoding unit 6 decodes the Morse signal from the receiving unit 3 into characters. Also, the CW decoding unit 6 estimates the transmission speed (the transmission speed of the other station) of the Morse signal from the receiving unit 3. The character display unit 7 displays the characters decoded by the CW decoding unit 6. The CPU 9 is a control device that controls each part of the transceiver 1. The memory 10 stores data, programs, etc. necessary for the communication processing of the transceiver 1, and is also used as a working area for the communication processing.

[0017] The code input device 8 is a device such as a keypad for inputting Morse code. As the code input device 8, for example, a paddle is used. The code input device 8 generates a dot output instruction signal and a dash output instruction signal corresponding to each of the dots and dashes constituting the Morse code according to the key operation by the operator. The dot output instruction signal is a signal for instructing to output a dot signal to the electric keyer 93 and has dot information. The dash output instruction signal is a signal for instructing to output a dash signal to the electric keyer 93 and has dash information.

[0018] 〈Configuration of the receiving unit〉 The receiving unit 3 includes an anti-aliasing filter 32, an A / D converter 33, a mixer 34, a downsampling filter 35, an IF filter 36, a normalization unit 37, and a demodulation unit 38. In FIG. 1, the A / D converter 33 is indicated by "A / D", and the downsampling filter 35 is indicated by "DS filter".

[0019] In the receiving unit 3, among the signals band-limited by the band-pass filter 11, only the signals in a predetermined frequency band pass through the anti-aliasing filter 32, and the signals are digitally converted by the A / D converter 33.

[0020] The anti-aliasing filter 32 is composed of a low-pass filter, and allows signals up to the frequency of 1 / 2 of the sampling clock (Nyquist frequency) to pass through when the A / D converter 33 samples the input signal.

[0021] The mixer 34 converts the signal after A / D conversion into a 0 Hz IF (baseband signal, I / Q signal) by mixing the signal with a local transmission frequency signal that matches the desired reception frequency. The CW pitch frequency is added to the local transmission frequency.

[0022] The downsampling filter 35 is composed of a low-pass filter, and converts the baseband signal into a narrowband signal by removing unnecessary components through downsampling. The IF filter 36 is composed of a band-pass filter (BPF) and extracts signals of surrounding frequencies to be received. For Morse signals, the frequency band to be extracted can be selected by the user using a BPF having a center frequency such as 500 Hz or 250 Hz.

[0023] The normalization unit 37 outputs a signal normalized to “0” and “1” by performing AGC (Auto Gain Control) processing on the signal output from the IF filter 36. The demodulation unit 38 outputs an audio signal of a desired frequency by performing predetermined demodulation processing on the signal. The frequency of the desired audio (received tone) is set at the CW pitch (for example, a frequency in the range of 300 Hz to 900 Hz). The above audio signal is output as Morse audio by a speaker (not shown).

[0024] 〈Configuration of CW Decoding Unit〉 The CW decoding unit 6 includes a downsampling filter 61, a mixer 62, a decoding filter 63, an amplitude conversion unit 64, a normalization unit 65, a key determination unit 66, and a character decoding unit 67. In FIG. 1, the downsampling filter 61 is indicated as a “DS filter”. The CW decoding unit 6 is composed of a digital signal processing circuit such as a DSP (Digital Signal Processor) or an FPGA (Field Programmable Gate Array).

[0025] The downsampling filter 61 is composed of a low-pass filter, and downsamples the signal output from the IF filter 36 so as to have the frequency required for decoding. The mixer 62 mixes the signal output from the downsampling filter 61 with a signal having a CW pitch, thereby canceling out the CW pitch mixed in the mixer 34 and converting it into a signal having a center frequency of 0 Hz.

[0026] The decode filter 63 is composed of a low-pass filter, and removes unnecessary signals so as to leave the CW carriers concentrated around 0 Hz. The decode filter 63 may be omitted, but it is preferably provided to enhance the noise resistance performance.

[0027] The amplitude conversion unit 64 converts the output signal of the decode filter 63 into an amplitude value by performing the operation of √(I 2 +Q 2 ). Thereby, the envelope of the output signal is detected, and an amplitude value depending on the reception intensity of noise in a no-signal state and an amplitude value depending on the reception intensities of a signal and noise in a signal state are obtained.

[0028] The normalization unit 65 is composed of an AGC circuit, and outputs a normalized signal that is normalized to be "0" in a no-signal state and "1" in a signal state based on the amplitude value output from the amplitude conversion unit 64.

[0029] The key determination unit 66 determines whether the state of the normalized signal from the normalization unit 65 is either "H" or "L", and determines the duration of the determined "H" and "L". The key determination unit 66 estimates the WPM (Words Per Minute) based on the duration, and smooths the WPM. The key determination unit 66 performs encoding based on the duration and the estimated WPM.

[0030] Here, WPM corresponds to the keying speed, which is the transmission speed of Morse signals. WPM is expressed as the number of occurrences of 50 dots (1 word) of Morse code per minute. Thus, the time of dots is reflected in WPM.

[0031] <Configuration of Key Determination Unit> The key determination unit 66 includes a binary determination unit 661, a duration determination unit 662, a WPM estimation unit 663 (estimation unit), a smoothing unit 664, and an encoding unit 665.

[0032] The binary determination unit 661 compares the state of the normalized signal with a certain threshold value (for example, 0.5). When the normalized signal is equal to or greater than the threshold value as a result of the comparison, the binary determination unit 661 determines that the state is “H” (key-on state), and when the normalized signal is less than the threshold value, it determines that the state is “L” (key-off state). The binary determination unit 661 outputs an amplitude signal having two values, “H” (maximum value) and “L”.

[0033] Here, the key-on state is the state where the operator turns on the key of the code input device at the other station, that is, the state where a dot or a dash is input. “H” is a keying signal representing the keying state of the code input device and includes dots and dashes of Morse code. Also, the key-off state is the state where the operator turns off the key of the code input device at the other station, that is, the state where no dot or dash is input (a state where an interval occurs). “L” is a non-keying signal representing the non-keying state by the code input device.

[0034] The duration determination unit 662 determines the durations of “H” and “L” by generating signals representing the respective durations of “H” and “L”. Specifically, the duration determination unit 662 determines the lengths of “H” and “L” through processes such as max hold, minimum hold, and averaging.

[0035] Based on the duration of "H" in the amplitude signal determined by the duration determination unit 662, the WPM estimation unit 663 estimates the WPM (the keying speed of the other party, the transmission speed of the other party). The WPM estimation unit 663 outputs the estimated WPM as the estimated WPM.

[0036] The smoothing unit 664 smooths the estimated WPM output from the WPM estimation unit 663. Since the estimation of the WPM is performed over a certain period, the accuracy of the estimated WPM can be improved by smoothing the estimated WPM.

[0037] The encoding unit 665 performs encoding to generate Morse code based on the durations of "H" and "L" determined by the duration determination unit 662. In the encoding, the encoding unit 665 sets a plurality of thresholds based on the estimated WPM output from the WPM estimation unit 663. As described above, since the time of the short dot is reflected in the estimated WPM, the threshold changes according to the time of the short dot.

[0038] The encoding unit 665 identifies the keying signal ("H") as either a short dot or a long dot by comparing the threshold with the above-mentioned duration, and also identifies the non-keying signal ("L") as either an inter-dot interval, an inter-character interval, or an inter-word interval. Here, the inter-dot interval has the same length as the length of the short dot. The inter-character interval has a length three times that of the short dot. The inter-word interval has a length seven times that of the short dot.

[0039] The threshold (the first threshold, the dot identification threshold) for identifying the short dot and the long dot is, for example, twice the length of the short dot. The threshold (the second threshold, the interval identification threshold) for identifying the inter-dot interval and the inter-character interval is, for example, twice the length of the short dot. The threshold (the third threshold, the interval identification threshold) for identifying the inter-character interval and the inter-word interval is, for example, five times the length of the short dot.

[0040] Note that if encoding is performed while the WPM estimation by the WPM estimation unit 663 is not complete, the correct estimated WPM cannot be obtained. Therefore, since the encoding unit 665 cannot set the threshold value appropriately, it cannot perform encoding appropriately. Thus, the encoding unit 665 performs encoding after the estimation of WPM is complete. Specifically, the encoding unit 665 holds the signal representing the duration until the estimation of WPM is complete, and performs encoding based on the held signal after the estimation of WPM is complete. Thereby, encoding can be appropriately performed with the threshold value set based on the correct estimated WPM.

[0041] The character decoding unit 67 collates the Morse code generated by the encoding of the encoding unit 665 with a dictionary and converts the Morse code into a character. The character decoding unit 67 outputs character code data as a result of the conversion.

[0042] 〈Configuration of CPU〉 The CPU 9 has a character display processing unit 91, an electric keyer 93 (control unit), and a setting unit 92. The character display processing unit 91, the setting unit 92, and the electric keyer 93 are functional blocks realized by the CPU 9 executing a predetermined program, respectively.

[0043] The character display processing unit 91 outputs character display data to the character display unit 7 based on the character code data from the character decoding unit 67 of the CW decoding unit 6. The character display unit 7 displays characters based on the display data.

[0044] The setting unit 92 sets the target value of the keying speed stored in the memory 10 based on the estimated WPM estimated by the WPM estimation unit 663 and smoothed by the smoothing unit 664. Specifically, the setting unit 92 sets the estimated WPM as the target value. Since the target value is set as a variable in the program for realizing the function of the electric keyer 93, the setting unit 92 sets the target value by changing the variable of the program stored in the memory 10 to the estimated WPM.

[0045] The target value of the memory 10 is reset when the power supply of the transceiver 1 is cut off. Also, the target value of the memory 10 is set to the default value when the power supply of the transceiver 1 is turned on. When the target value is newly set, the target value of the memory 10 is overwritten with the new value.

[0046] When a dot output instruction signal or a dash output instruction signal is input from the code input device 8 to the electric keyer 93, the electric keyer 93 adjusts the keying speed by generating a dot signal or a dash signal of a specified length based on the reference clock signal. The specified length of each of the dot signal and the dash signal is based on the period of the reference clock signal. Also, the electric keyer 93 controls the keying speed (local transmission speed) when transmitting the Morse signal from the local station so as to become the target value set in the memory 10.

[0047] Note that the electric keyer 93 is provided as a functional block realized by the CPU 9 executing a program, but it may be provided as a dedicated circuit.

[0048] <Configuration of the transmission unit> The transmission unit 4 includes a keying circuit 41, an upsampling filter 42, a mixer 43, a D / A converter 44, and an anti-aliasing filter 45. In FIG. 1, the D / A converter 44 is indicated by "D / A", and the upsampling filter 42 is indicated by "US filter".

[0049] The keying circuit 41 generates a transmission high-frequency signal (CW signal) by superimposing a dot signal or a dash signal from the electric keyer 93 on a carrier of a predetermined frequency. The transmission high-frequency signal is subjected to respective processes by the upsampling filter 42, the mixer 43, the D / A converter 44, and the anti-aliasing filter 45, and is output to the transmit / receive switching unit 5.

[0050] <Control of keying speed by the transceiver> Figure 2 is a flowchart showing the procedure (wireless communication method) for controlling the keying speed by the transceiver 1.

[0051] As shown in Figure 2, first, the WPM estimation unit 663 estimates the WPM (opposite station transmission speed), which is the keying speed of the opposite station, based on the duration of "H" in the amplitude signal determined by the duration determination unit 662 for the Morse signal received from the opposite station. Specifically, the WPM estimation unit 663 estimates the WPM as follows and outputs the estimated WPM as the estimated WPM.

[0052] First, the WPM estimation unit 663 identifies short points and long points based on the duration of "H" representing short points and long points (step S1, estimation step). The WPM estimation unit 663 determines that it is a long point when the duration of "H" exceeds the threshold value, and determines that it is a short point when the duration of "H" is less than or equal to the threshold value. Regarding the threshold value, since the long point has a length three times that of the short point, for example, a length twice that of the short point is set.

[0053] The WPM estimation unit 663 estimates the time of the identified short points, and based on the estimated time of the short points, calculates the number of times a predetermined number (for example, 50 (1 word)) of short points appear in one minute (prescribed time). The WPM estimation unit 663 holds the duration of "H" during the period required for estimating the WPM, and estimates the time of the short points by statistically processing the held duration. Examples of statistical processing methods include a method of obtaining the average value of the durations over a certain period, a method of tentatively classifying short points and long points by comparing the duration with the average value as the threshold value, and obtaining the average value for the classified short points and long points.

[0054] Subsequently, the setting unit 92 sets the target value of the keying speed in the memory 10 based on the estimated WPM estimated by the WPM estimation unit 663 (step S2, setting step). For example, the setting unit 92 sets the estimated WPM as the target value of the keying speed.

[0055] The electric keyer 93 controls the keying speed of its own station so as to reach the target value set in the memory 10 (step S, control step). Specifically, based on the dot output instruction signal or dash output instruction signal input from the code input device 8, the electric keyer 93 generates a dot signal or dash signal based on the reference clock signal. In generating the dot signal or dash signal, the electric keyer 93 changes the frequency of the reference clock signal to a frequency corresponding to the target value set in the memory 10, and assigns dots and inter-dot intervals to the half period of the reference clock signal.

[0056] <Effect by Transceiver> The transceiver 1 according to this embodiment includes a WPM estimation unit 663, a setting unit 92, and an electric keyer 93. The WPM estimation unit 663 estimates the keying speed (remote station transmission speed) of the remote station of the Morse signal based on the Morse signal received from the remote station. The setting unit 92 sets a target value of the keying speed (local station transmission speed) of the Morse signal based on the estimated keying speed of the remote station. The electric keyer 93 controls the keying speed of its own station to reach the target value.

[0057] In the above configuration, the keying speed of the local station is set based on the estimated keying speed of the remote station. Thereby, the labor of the user for adjusting the keying speed of the local station to match the keying speed of the remote station can be saved.

[0058] The WPM estimation unit 663 identifies dots and dashes in the Morse code based on the duration of "H" in the amplitude signal having two values of "H" and "L" obtained from the Morse signal received from the remote station. Further, the WPM estimation unit 663 estimates the WPM by calculating the number of times a predetermined number of dots appear within a specified time based on the identified dots.

[0059] According to the above configuration, the WPM can be estimated by simple processing.

[0060] Even after the target value is set by the setting unit 92, the WPM estimation unit 663 continues to estimate the keying speed of the other party. The transceiver 1 includes an encoding unit 665. The encoding unit 665 identifies short dots and long dots, which are components of Morse code, by comparing the duration of "H" with a first threshold value (dot discrimination threshold value) determined based on the keying speed of the other party estimated by the WPM estimation unit 663. Further, the encoding unit 665 performs encoding to identify a plurality of different intervals, which are components of Morse code, by comparing the duration of "L" with a second threshold value (interval discrimination threshold value) and a third threshold value (interval discrimination threshold value) determined based on the keying speed transmission speed of the other party.

[0061] When the Morse signal from the other party is generated by an electric keyer at the other party, the Morse signal is received at a constant keying speed of the other party. However, when the Morse code is generated without using an electric keyer, the keying speed of the other party is likely to vary according to the variation in the speed of the operation by which the operator of the other party inputs the code. For this reason, the possibility that the encoding by the encoding unit using the first threshold value, the second threshold value, and the third threshold value determined based on the estimated WPM is not correctly performed increases.

[0062] In the above configuration, even after the target value of the keying speed of the own station is set by the setting unit, the estimation of the keying speed of the other party continues. As a result, the estimated WPM also changes according to the change in the actual keying speed of the other party. Therefore, by using the continuously estimated estimated WPM, it is possible to reduce the possibility that the encoding by the encoding unit 665 is not correctly performed.

[0063] 〔Example of Realization by Software〕 The function of the transceiver 1 (hereinafter referred to as the "device") can be realized by a communication control program for causing a computer to function as the device. The communication control program is a program for causing a computer to function as each control block of the device (particularly the electric key 93 and the setting unit 92).

[0064] As described above, the WPM estimation unit 663 and the encoding unit 665 are realized by a digital signal processing circuit, but may also be realized by a communication control program together with the electric key 93 and the setting unit 92. However, in order to perform signal processing in real time without being affected by other programs executed in parallel with the communication control program, the WPM estimation unit 663 and the encoding unit 665 are preferably realized by a digital signal processing circuit.

[0065] In this case, the device includes, as hardware for executing the program, a computer having a CPU 9 as at least one control device and a memory 10 as at least one storage device. By executing the communication control program by this CPU 9 and memory 10, each function described in the above embodiment is realized.

[0066] The communication control program may be recorded on one or more computer-readable recording media, not temporarily. This recording medium may or may not be provided in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0067] Also, part or all of the functions of each of the above control blocks can be realized by a logic circuit. For example, an integrated circuit in which a logic circuit functioning as each of the above control blocks is formed is also included in the scope of the present invention.

[0068] 〔Supplementary Notes〕 The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. Also, embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

Explanation of Signs

[0069] 1 Transceiver (Wireless Communication Device) 8 Symbol Input Device 92 Setting Unit 93 Electric Keyer (Control Unit) 663 WPM Estimation Unit (Estimation Unit) 665 Encoding Unit

Claims

1. A wireless communication device for transmitting and receiving Morse signals, comprising: an estimation unit that estimates the transmission speed of a Morse signal from a counterpart station based on the Morse signal received from the counterpart station; a setting unit that sets a target value for the transmission speed of the Morse signal at the local station based on the estimated transmission speed of the counterpart station; a control unit that controls the transmission speed at the local station so as to reach the set target value.

2. The estimation unit identifies short points and long points in a Morse code based on the duration of the maximum value in an amplitude signal having two values, a maximum value and a minimum value, obtained from the Morse signal received from the counterpart station, and estimates the transmission speed of the counterpart station by calculating the number of times a predetermined number of the short points appear within a specified time. The wireless communication device according to Claim 1.

3. The estimation unit continues to estimate the transmission speed of the counterpart station even after the target value is set by the setting unit. The wireless communication device further comprises an encoding unit that performs encoding to identify short points and long points, which are components of the Morse code, by comparing the duration of the maximum value with a point identification threshold value determined based on the transmission speed of the counterpart station estimated by the estimation unit, and to identify a plurality of different intervals, which are components of the Morse code, by comparing the duration of the minimum value with an interval identification threshold value determined based on the transmission speed of the counterpart station. The wireless communication device according to Claim 2.

4. A communication control program for causing a computer to function as the estimation unit and the setting unit in the wireless communication device according to any one of Claims 1 to 3.

5. A wireless communication method for transmitting and receiving Morse signals, comprising: an estimation step of estimating the transmission speed of a Morse signal from a counterpart station based on the Morse signal received from the counterpart station; a setting step of setting a target value for the transmission speed of the Morse signal at the local station based on the estimated transmission speed of the counterpart station; a control step of controlling the transmission speed at the local station so as to reach the set target value.

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