JPH04196945A - Multilevel modulating/demodulating communication method and system - Google Patents

Abstract

PURPOSE:To effectively utilize a frequency by realizing a modulated frequency as a value dividing entire transmission capacity T with a value, which is not a natural number such as 5/2, 7/3 and 7/2 or the like and utilizing an excess band by transmitting information as the combination of plural phase planes. CONSTITUTION:In the case of N=2, M=4, P=1, Q=1, A1=24 and A2=24 for the N number (two) values A1 and A2, a transmitting data train conversion circuit 10 converts a transmitted signal 100 to 9 (MXN+P) trains of transmitting data trains 1. A data conversion circuit 1 converts the transmitting data trains 1 to the two pairs (N pairs) respectively having the 5 (M+Q) trains of transmitting parallel data trains 2A and 2B. A parallel/serial conversion circuit 12 converts the transmitting parallel data trains 2A and 2B to the 5 (M+Q) trains of transmitting serial data trains 3. A multilevel modulation circuit 13 executes 24-value multilevel orthogonal modulation according to the 5 trains of the transmitting serial data trains 3 and outputs a modulated signal 4. From the modulated signal 4, a received signal 101 is reproduced through a multilevel demodulation circuit 23, serial/parallel conversion circuit 22, inverse conversion circuit 21 and data train number inverse conversion circuit 20.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multilevel modulation/demodulation communication method and system for digital microwave communication.

[Conventional technology]

Conventionally, this type of multilevel modulation/demodulation communication system treats each phase plane that is transmitted continuously in a time series as being independent.

[Problem to be solved by the invention]

The conventional multilevel modulation/demodulation communication method and its system described above independently handle information on continuous phase planes as a time series, so they are limited to handling 2'' information on one phase plane, where n is a natural number. In other words, since n was limited to a natural number, the overall transmission capacity was T (bps
), the modulation frequency becomes a discrete value of T/n (Hz), which has a drawback in terms of effective frequency utilization.

[Means to solve the problem]

In the multilevel modulation/demodulation communication method of the present invention, M and N are integers equal to or greater than 2, P is an integer equal to or greater than 1 and less than N, and Q is equal to or greater than 1. or an integer greater than 1, convert the input single or multiple binary data strings into M×N+P strings, and convert N values A1゜A2, . . . AN to 2 M+P/N, respectively.
Assuming that the product from A1 to AN is approximately equal to 2M to +2, the binary data string of M×N+P columns is expressed as a combination of N sets of binary data strings of M+Q columns corresponding to the values A1 to AN, respectively. Each of these N sets of binary data strings of M+Q columns is converted into one set of binary data strings of M+Q columns, and this set of binary data strings of M+Q columns is input, and each time Then, a number of signal points corresponding to the value A l□ A N are arranged on the phase plane to perform multilevel modulation.

In the multilevel modulation/demodulation communication system of the present invention, M and N are integers equal to or greater than 2, P is an integer equal to or greater than 1 and less than N, and Q is an integer equal to or greater than 1. or an integer greater than 1, convert the input single or multiple binary data strings into M×N+P strings, and N
Values of A1゜A2. ...AN 2M+P/N each
Assuming that the product from A, to AN is approximately equal to 2 M×N+P, the M×N+P binary data string is divided into N sets of M+Q binary data strings corresponding to the values A and AN, respectively. A data conversion circuit converts each of these N sets of M+Q binary data strings into a set of M+Q binary data strings, and the data outputted from the data conversion circuit is The multilevel modulation circuit receives a set of M+Q binary data strings as input and arranges a number of signal points corresponding to the values A1 to AN on the phase plane at each time.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention, where N=2
．． M=4. P=1. Q=1. The case where A1=24 and A2=24 is shown.

The transmission data string conversion circuit 10 converts the transmission signal 100 into a transmission data string 1 of nine columns. The data conversion circuit 11 converts the transmission data string 1 into two sets of transmission parallel data strings 2A and 2 each having 5 columns.
Convert to B. The parallel-to-serial conversion circuit 12 converts the transmitted parallel data strings 2A and 2B into five transmitted serial data strings 3. The multilevel modulation circuit 13 generates 24
Multilevel orthogonal modulation is performed and a modulated signal 4 is output.

The multilevel demodulation circuit 23 inputs the modulated signal 4 and outputs a received demodulated data string 5. The serial/parallel conversion circuit 22 receives the demodulated data string 5 as input and outputs received parallel data strings 6A and 6B. The inverse conversion circuit 21 receives the received parallel data strings 6A and 6B as input, and outputs a received data string 9 as a nine-column binary signal. The data string number inverse conversion circuit 20 reproduces the received signal 101 from the received data string 9.

FIG. 2 is a time chart of the operation on the transmitting side in the embodiment shown in FIG.

Transmission data string 1, which is a binary signal with nine columns, is converted by a data conversion circuit 11 into two sets of transmission parallel data strings 2A and 2B, which are binary signals with five columns each.
As a result, the bit rate is doubled and the data is converted into a transmission serial data string 3. Each bit of the transmitted parallel data strings 2A and 2B is inserted into time slots A and B of the serial data string 3.

In the case of the embodiment described above, 24×24=576 types of information can be expressed as a combination of two phase planes of 24-value modulation. Since 576 is larger than 29=512, data for 9 hits can be transmitted in two phase planes. Approximately 4.5 hits are transmitted in one phase plane, and 16QA as a conventional example.
It is possible to provide an intermediate modulation and demodulation method between M and 32QAM.

Further, even when the values of N, M, P, Q, and An are different from those mentioned above, the present invention can be applied to obtain the same effect.

〔Effect of the invention〕

As explained above, the present invention transmits information as a combination of a plurality of phase planes, thereby achieving a value obtained by dividing the overall transmission capacity T by a value that is not a natural number, such as 5/2° 7/3.7/2. The modulation frequency can be realized as , and the effective use of frequency can be realized by using the surplus band.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a time chart of each signal in the embodiment shown in FIG. 10... Data string number conversion circuit, 11... Data conversion circuit, 12... Parallel-serial conversion circuit, 13... Multi-level modulation circuit, 20... Data string number inverse conversion circuit, 21... Data Inverse conversion circuit, 22...Serial-to-parallel conversion circuit, 23. Multi-level demodulation circuit.

Claims (1)

[Claims] 1, M and N are integers equal to or greater than 2, P is equal to or greater than 1, and N
Q is an integer equal to or greater than 1, and the input single or multiple binary data strings are M×
Convert to N+P column, N values A_1, A_2,...A
Each _N is approximately equal to 2^M^+^P^/^N A
Assuming that the product from _1 to A_N is equal to 2^M^×^N^+^P, the binary data string of the M×N+P columns is divided into N sets of binary data of M+Q columns corresponding to the values A_1 to A_N, respectively. Convert each of these N sets of binary data strings of M+Q columns to one set of binary data strings of M+Q columns, and convert this set of binary data strings of M+Q columns to A multi-value modulation/demodulation communication method characterized in that a number of signal points corresponding to values A_1 to A_N are arranged on a phase plane at each time as an input, and multi-value modulation is performed. 2, M and N are integers equal to or greater than 2, P is equal to or greater than 1, and N
Q is an integer equal to or greater than 1, and the input single or multiple binary data strings are M×
Convert to N+P column, N values A_1, A_2,...A
Each _N is approximately equal to 2^M^+^P^/^N A
Assuming that the product from _1 to A_N is equal to 2^M^×^N^+^P, the binary data string of the M×N+P columns is divided into N sets of binary data of M+Q columns corresponding to the values A_1 to A_N, respectively. a data conversion circuit that converts each of these N sets of binary data strings of M+Q columns into one set of binary data strings of M+Q columns; A multi-value modulation circuit that receives a set of M+Q binary data strings as input and arranges a number of signal points corresponding to values A_1 to A_N on a phase plane at each time. Modulation and demodulation communication system.