JPH1075234A - Transmitter/receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmitter/receiver with which handling is facilitated in the case of transmitting/receiving and decoding data and efficiency in encoding is improved when the same code bit is prevented from being generated continuously more than a prescribed number in the case of encoding. SOLUTION: When transmission data are formed from the transmission information of characters, etc., an encoding part 1 compares the signal levels of 4th and 5th bits in the data and when these signal level are equal, this encoding part forms transmission data inverting all the bits from the next bit of the 5th bit to the 8th bit and forms inversion information data having inversion information showing whether the bits of the formed transmission data are inverted or not. A decoding part 7 reproduces transmission information on the side of transmission from the inversion information data from the transmission side and the transmission data having that inversion information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting / receiving apparatus for transmitting data by encoding and decoding transmission information such as characters.

[0002]

2. Description of the Related Art Conventionally, a transmission / reception device of a plurality of channels for transmitting / receiving data by wireless communication, when transmitting data,
As shown in FIG. 6, an encoding unit 51 encodes transmission information (digital signal) such as characters according to a predetermined rule to form transmission data, and a modulation unit 52 modulates the encoded transmission data into an analog signal. And then RF (Radio Freqen
cy) The unit 53 amplifies the transmission data modulated into an analog signal, and further superimposes the transmission data on a carrier wave to form an antenna 5
8.

On the other hand, in the transmitting / receiving apparatus described above, when receiving data, the RF unit 53 amplifies a reception frequency (analog signal) received by the antenna 58, converts the signal into a predetermined frequency band, and converts the signal into a predetermined frequency band. The demodulation unit 54 converts the signal converted to the frequency band into a demodulated signal (digital signal),
Thereafter, the decoding unit 57 is configured to decode the demodulated signal input via the AC capacitor 55 and the amplifier unit 56 so that the CPU (not shown) can process the demodulated signal.

However, in such a conventional transmission / reception device, when the demodulated signal formed by the demodulation section 54 passes through the AC capacitor 55, the AC capacitor 55 cuts off the DC component. In the case of a signal waveform having a continuous code, the signal waveform is distorted as shown in (1). For this reason, when the decoding unit 57 decodes the distorted signal waveform, bit blur occurs, and accurate transmission data cannot be obtained. There was an inconvenience that it was difficult to reproduce.

Therefore, in order to solve such inconvenience, in a conventional transmitting / receiving apparatus, when encoding is performed so that a signal in which the same code which is apt to cause bit blurring is continuous is not transmitted, the encoding unit 51 uses the same code bit. When a predetermined number of consecutive transmission data are received, a method of inserting an inversion bit into the consecutive same sign bits is adopted.

More specifically, as shown in FIG. 7, if the encoding unit 51 receives transmission data in which the same code continues for 6 bits before encoding, as shown in FIG. A signal encoded by inserting bits is transmitted.

[0007] In addition to the method of inserting the inverted bit, as shown in FIG.
No. 1 employs a so-called Manchester code conversion system in which each of a high-level bit and a low-level bit is converted by a 2-bit signal consisting of a high-level bit and a low-level bit.

[0008]

However, as described above, in the case where the same code is continuously received before transmission and transmission data is received, the transmission / reception apparatus adopting the method of inserting an inverted bit is not encoded. Since the total number of bits of the data does not have regularity with respect to the original signal, the total bits cannot be calculated, and there is a problem that handling in data transmission / reception and decoding becomes complicated.

In addition, since the total number of bits after encoding does not become a multiple of 8 bits, there is a problem that a transmission / reception apparatus using a start-stop synchronization method cannot be handled.

In a transmitting / receiving apparatus adopting the Manchester encoding method, unlike the above-described method in which the inverted bit is inserted, the total number of encoded bits can be calculated.
There is a problem that the total number of encoded bits is twice that of the original signal, and the encoding efficiency is poor.

The present invention has been made in view of the above-described problems, and when encoding is performed so that the same code bit does not continuously occur more than a predetermined number, handling in data transmission / reception and decoding is easy, and An object of the present invention is to provide a transmission / reception device with high encoding efficiency.

[0012]

In order to achieve the above-mentioned object, according to the present invention, there is provided an encoding means for encoding transmission information such as characters to form transmission data; In a transmitting / receiving apparatus provided with decoding means for reproducing transmission information such as characters from data, when the encoding means forms transmission data from the transmission information such as characters, a signal between a predetermined bit and the next bit in the data is transmitted. Compare the levels, and if they are the same signal level, invert all bits from the first bit to the above-mentioned predetermined bit, or invert all bits from the next bit to the above-mentioned predetermined bit to the last bit Forming the transmission data, and forming inversion information data having inversion information indicating whether or not the formed transmission data is bit-inverted. And inverting the information data, and a transmission data having the inverted information, characterized in that it reproduces the transmitted information on the transmission side.

According to a second aspect of the present invention, in the first aspect of the present invention, when the encoding means inverts the bits of the transmission data, the encoding means makes half or almost half the bits forming the transmission data. It is characterized by the following.

According to a third aspect of the present invention, in the first aspect of the present invention, the encoding means forms a predetermined number of the transmission data and forms inversion information data having inversion information corresponding thereto. It is characterized by.

According to a fourth aspect of the present invention, in the third aspect of the present invention, when the encoding means does not form a predetermined number of the transmission data, a dummy is stored in the inversion information data. And

A fifth aspect of the present invention is characterized in that, in the first to fourth aspects of the present invention, the transmission / reception device synchronization system is a start-stop synchronization system.

According to the present invention, when transmission data is formed from transmission information such as characters, the signal level of a predetermined bit in the data is compared with the signal level of the next bit. The transmission data is formed by inverting all the bits from the predetermined bit to the predetermined bit or by inverting all the bits from the next bit to the last bit of the predetermined bit. The occurrence of consecutive codes is reduced.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a transmitting / receiving apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of an embodiment of a transmitting / receiving apparatus according to the present invention.

The transmission / reception apparatus of this embodiment employs a start-stop synchronization method, and as described in detail later, an encoding unit 1 for encoding transmission information such as characters to form transmission data; A modulation unit 2 for modulating transmission data formed by the data block formation unit 2 into an analog signal, an RF unit 3 described later in detail, and a reception signal from another transmission / reception device obtained via the RF unit 3 are converted into a digital signal. A demodulation unit 4, an AC capacitor 5 for reducing the variation of the digital signal output from the demodulation unit 4, an amplifier unit 6 for amplifying the signal, and a decoding unit 7 described in detail below.
An antenna 9 is provided.

As shown in FIG. 2A, the encoding unit 1 is configured to form standardized and compressed transmission information into transmission data A consisting of binary encoded one byte. .

As shown in FIG. 2 (b), the encoding unit 1 generates a signal level of the fourth bit (D in the figure) and a signal level of the fifth bit (the figure) in the formed transmission data A. E)
And when the signal level is the same (D = E), all the bits from the fifth bit to the last bit, the eighth bit (E, F, G, H in the figure), are inverted. While the new transmission data A is formed, if the signal level is not the same (D ≠ E), the original transmission data A is left as it is.

Here, in the case of D = E, “e, f, g, h” described in the fifth to eighth bits in the newly formed transmission data A is the original transmission data. This indicates that "E, F, G, H" in A is inverted.

Further, after forming the transmission data A, the encoding unit 1 stores the transmission data A in a buffer.
Is stored in the four buffers, and it is configured to form inverted information data B for storing information (hereinafter referred to as inverted information) indicating whether or not each of the four transmission data A is bit-inverted. Have been.

Here, the inversion information data B will be described in more detail. As shown in FIG. 3A, the inversion information data B includes inversion information of the transmission data of # 1 in the first bit and the second bit. # 2 in the third and fourth bits
The fifth bit and the sixth bit store the inverted information of the # 3 transmission data, and the seventh and eighth bits store the inverted information of the # 4 transmission data.

When the inversion information is "1, 0", it indicates that all the fifth to eighth bits in the corresponding transmission data A are inverted, and when the information is "0, 1", Indicates that they are not inverted, or that a dummy indicating that there is no transmission data at a predetermined byte position is displayed.

Further, when the encoding unit 1 forms the inverted information data B, as shown in FIG. 3B, the encoding unit 1 places the inverted information data B at the top, and in the order of the formed transmission data A (# 1).
To # 4), a start bit indicating the first bit position of the bit string of each data and a stop bit indicating the last bit position are added and output to the modulation unit 2.

When the transmission data A is less than 4 bytes, for example, when there is only transmission data A of # 1 and # 2 as shown in FIG. The inversion information of the transmission data A is stored left-justified (in order from the first bit) and then stored to form inverted information data in which a dummy is stored.

When transmitting the transmission data, the RF unit 3 amplifies the transmission data modulated into an analog signal by the modulation unit 2 and transmits the amplified data from the antenna 8. 8 is configured to amplify the reception frequency (analog signal) received and convert it to a predetermined frequency band.

When receiving a data string received from another transmitting apparatus via the RF unit 3, demodulation unit 4, AC capacitor 5 and amplifier unit 6, the decoding unit 7 stores the received data string in the inverted information data B. Based on the inversion information, the fifth to eighth bits of each of the following transmission data A are inverted so that the state in which the encoding unit 1 has been inverted is returned to the original state in which it is not inverted. ing.

Next, the operation of the transmitting / receiving apparatus of this embodiment will be described separately for a transmitting operation and a receiving operation.

(1) Transmission Operation Hereinafter, in order to specifically describe the transmission operation, as shown in FIG. 4, "11110000", "00000111",
A case will be described as an example where four pieces of transmission information consisting of “00000111” and “00110100” are transmitted.

First, the encoding unit 1 sets "111100
When the transmission information of "00" is formed, it is determined whether or not the transmission information is bit-inverted.

That is, since the content of the fourth bit and the content of the fifth bit of the formed transmission information are not the same, the encoding unit 1 stores the transmission information “11110000” as it is as the transmission data A in the buffer. .

The encoding unit 1 transmits the transmission data A to the second transmission information “00000111” formed subsequently.
Is formed, it is determined whether or not the bit should be inverted.

In this case, since the content of the fourth bit and the content of the fifth bit of the transmission information are the same, the encoding unit 1
Determines that all the bit contents from the fifth bit to the eighth bit should be inverted, and “00001000” is obtained by inverting the fifth bit to the eighth bit in the transmission information.
Is stored in the buffer as transmission data.

Subsequently, the encoding unit 1 similarly sequentially transmits the third transmission information “00000011” and the fourth transmission information “00110100” to the transmission data A and “0011100” of the transmission data A “0001100”.
The transmission data A of 0100 ″ is formed and stored in the buffer.

By the way, the third transmission data A is formed by inverting the contents of the fifth to eighth bits in the transmission information, and the fourth transmission data A is the content of the transmission information as it is. belongs to.

When the four pieces of transmission data A are stored in the buffer in this way, the encoding unit 1 next converts the fourth transmission data A “00110100” from the first transmission data A “11110000”. The inversion information data B is formed based on the information of the bit inversion required for the formation.

That is, the encoding unit 1 is “non-inverted” when forming the first transmission data A, “inverted” when forming the second transmission data A, and the third transmission data. When forming the data A, “inverted” and the fourth transmission data A
Is formed, the inverted information data B of "011101001" is formed based on the determination of "non-inverted".

The encoding unit 1 outputs the inversion information data B “011
When 01001 ″ is formed, the first to fourth transmission data A to the fourth transmission data A are transmitted to the modulating unit 2 with the start bit and the stop bit added in order from the inverted information data B.

The reason why the start bit and the stop bit are added to each of the data A and B is that the receiving side of the data needs to perform start-stop synchronization as a synchronization timing when decoding from the received data. It is.

That is, as shown in FIG. 5, the encoding unit 1 adds “1” as the start bit at the beginning and “0” as the stop bit at the end in the inverted information data B composed of “011101001”. "10110100
10 in the first transmission data A consisting of "1111100000", and "11111100000" in the transmission data A consisting of the second "00001000".
0000000 "to the third" 000001100 "
In the transmission data A consisting of “1000011000”
Is the transmission data A consisting of the fourth "00110100"
Then, “1001101000” is output to the modulation unit 2.

Upon receiving the inverted information data to which the start bit and the stop bit are added and the first to fourth transmission data from the encoder 1, the modulator 2 modulates these into analog signals and converts them to RF signals. Output to unit 3.

Thereafter, the RF unit 3 amplifies the modulated signal so that it can be transmitted by radio waves, superimposes the modulated signal on a carrier wave, transmits the signal via the antenna 8, and ends the transmission operation.

(2) Reception Operation Hereinafter, in order to specifically describe the reception operation, “1011010010” and “111110000” shown in FIG.
0 "," 10000100000 "," 100000110 "
The case of received data consisting of “00” and “1001101000” will be described as an example.

When receiving the received frequency from the antenna 8, the RF unit 3 amplifies the received frequency, removes the carrier component, and converts the received data (analog signal) converted to a predetermined frequency band into a demodulator 4. Output to

The demodulator 4 demodulates the data received from another transmitting / receiving device via the RF unit 3 into a digital signal.

Then, the demodulated signal is "10110
10010 "," 11111100000 "," 1000
010000 "," 1000011000 "and" 1
It becomes a digital signal of "0011101000".

The decoding section 7 decodes data received from another transmitting / receiving apparatus, obtained from the demodulator 4 via the AC conductor 5 and the amplifier section 6.

That is, when recognizing the start bit, the decoding section 7 removes the start bit and the stop bit, and extracts the data.

That is, the decoding unit 7 outputs “0110100
1 "," 11110000 "," 00001000 ",
The data "000001100" and "00110100" are extracted and stored in a buffer.

Thereafter, the decoding unit 7 outputs the first data “0”.
1101001 "is inspected, and it is determined whether or not the subsequent data needs to be bit-inverted. If the data needs to be bit-inverted, bit inversion is performed to reproduce the transmission information from the transmission destination. The receiving operation ends.

According to the transmitting and receiving apparatus of this embodiment, when the encoding unit 1 forms transmission data from transmission information such as characters,
The signal level of a predetermined bit in the data is compared with the signal level of the next bit. If the signal level is the same, all bits from the first bit to the predetermined bit are inverted, or the bit next to the predetermined bit is Since the transmission data in which all the bits from the first bit to the last bit are inverted is formed, the occurrence of the same code in the formed transmission data A continuously decreases.

Therefore, the total number of bits of the encoded data has regularity with respect to the original signal, the total bits cannot be calculated, and the handling in data transmission / reception and decoding is easy.

In particular, the total number of bits after encoding can be a multiple of 8 bits, and in particular, the start-stop synchronization method can be employed.

The present invention has been made in view of the above-described problems, and when encoding is performed such that a predetermined number or more of the same code bits are not continuously generated, handling in data transmission / reception and decoding is easy, and An object of the present invention is to provide a transmission / reception device with high encoding efficiency.

The transmission / reception apparatus of this embodiment employs the start-stop synchronization method in the bit synchronization method. However, it is also possible to adopt the start-stop synchronization method, the character synchronization method, and the flag synchronization method in the block synchronization. Not even.

The transmitting / receiving apparatus of this embodiment performs transmission / reception with wireless communication, but can also be used for wired communication.

Further, in the transmitting / receiving apparatus of this embodiment, the inverted bits are the fifth to eighth bits, but it goes without saying that the inverted bits may be the first to fourth bits.

[0061]

As described above, according to the present invention, when transmission data is formed from transmission information such as characters, the signal level of a predetermined bit in the data is compared with the signal level of the next bit. Since transmission data is formed by inverting all bits from the first bit to a predetermined bit or by inverting all bits from the next bit to the last bit of the predetermined bit, the formed transmission data A That the same sign occurs successively is reduced.

Accordingly, the total number of bits of the encoded data has a regularity with respect to the original signal, the total bits cannot be calculated, and the handling in data transmission / reception and decoding is easy.

In particular, the total number of bits after encoding can be a multiple of 8 bits, and in particular, the start-stop synchronization method can be employed.

Further, it is not necessary to adopt the Mancha-Esta code conversion method as in the prior art, and the coding efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a transmitting / receiving apparatus according to the present invention.

FIG. 2 is an explanatory diagram of transmission data formed by an encoding unit in FIG. 1;

FIG. 3 is an explanatory diagram of inversion information data and transmission transmission data formed by an encoding unit in FIG. 1;

FIG. 4 is an explanatory diagram for explaining the operation of the transmission / reception device of the embodiment.

FIG. 5 is an explanatory diagram for explaining the operation of the transmitting / receiving device of the embodiment.

FIG. 6 is a block diagram showing a configuration of a conventional transmitting / receiving apparatus.

FIG. 7 is a timing chart for explaining a bit insertion method employed in a conventional transmitting / receiving apparatus.

FIG. 8 is a timing chart for explaining a manchastor method employed in a conventional transmitting / receiving apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Encoding part 2 Modulation part 3 RF unit 4 Demodulation part 5 AC capacitor 6 Amplifier part 7 Decoding part 8 Antenna

Claims (5)

[Claims] 1. A transmission / reception apparatus comprising: an encoding unit that encodes transmission information such as characters to form transmission data; and a decoding unit that reproduces transmission information such as characters from received transmission data. When the conversion means forms transmission data from the transmission information such as the characters, the predetermined bit in the data is compared with the signal level of the next bit. Or inverts all bits up to, or forms transmission data in which all bits from the next bit to the last bit of the predetermined bit are inverted, and inverts whether the formed transmission data has been bit inverted. Forming inverted information data having information, wherein the decoding means transmits the inverted information data from the transmitting side;
A transmission / reception device that reproduces transmission information on the transmission side from transmission data having the inverted information. 2. The transmission / reception apparatus according to claim 1, wherein when the encoding means inverts the bits of the transmission data, the encoding means sets the transmission data to half or substantially half of the bits forming the transmission data. 3. The apparatus according to claim 1, wherein said encoding means forms a predetermined number of said transmission data and forms inversion information data having inversion information corresponding thereto.
The transmitting / receiving device according to any one of the preceding claims. 4. The transmission / reception apparatus according to claim 3, wherein said encoding means stores a dummy in said inverted information data when a predetermined number of said transmission data is not formed. 5. The synchronous system according to claim 1, wherein the synchronous system is a start-stop synchronous system.
5. The transmitting / receiving device according to any one of claims 1 to 4.