JP2000174667A - Frequency hopping transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reproducibility of data even when interference is present and to accurately transmit information in the case that a data transfer speed is high or in the case of wanting to accelerate the data transfer rate. SOLUTION: In this transmission system, a transmitter 10 is provided with a data string order rearrangement circuit 13 for rearranging the order of data strings outputted from an error correction control processing part 12 so as to distribute the successive data of the same number as the number of hopping frequencies used in the system of the data strings to the mutually different hopping frequencies and outputting them to a data modulation circuit 14. Then, a receiver 20 is provided with a data string order restoration circuit 25 for restoring the order of the data strings from a data demodulation circuit 24 and outputting them to an error correction circuit 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency hopping transmission system, and more particularly to a frequency hopping transmission system for transmitting data while shifting a transmission frequency according to a predetermined frequency hopping pattern.

[0002]

2. Description of the Related Art Among data transmission systems, there is a frequency hopping transmission system that performs data transmission while using several frequencies within a used frequency band and sequentially shifting to these frequencies according to a predetermined pattern. FIGS. 4A and 4B are block diagrams of a typical conventional example of the frequency hopping transmission system. The frequency hopping transmission system of this example includes a transmitter 10x and a receiver 20x, the details of which are as follows. Transmitter 10x
Is an input circuit 11 for sequentially inputting the data DTi, an error correction control processing unit 12 for performing processing such as error correction encoding on the input data DTi, and outputting the data, and the output data of the error correction control processing unit 12 A data modulation circuit 14 for generating a modulated transmission intermediate frequency signal IFt; and a transmission frequency hopping pattern signal FHP for designating the transmission intermediate frequency signal IFt to a preset hopping pattern.
a transmission-side frequency shift circuit 15 that shifts to a frequency of a radio frequency band based on t to generate and output a frequency hopping signal FHS, a signal transmission unit 16 that radiates the frequency hopping signal FHS from the antenna 17 as radio waves, The processing operation of the error correction control processing unit 12 and the data modulation circuit 14 is controlled, and the frequency hopping pattern signal FHP
and a transmission control unit 18x that outputs t to control the processing operation of the transmission-side frequency shift circuit 15.

The receiver 20x receives a radio wave transmitted from the transmitter 10x and receives a frequency hopping signal FHS.
Amplifying unit 2 which receives and amplifies and outputs the signal with antenna 21
2 and the frequency of the frequency hopping signal (FHS) from the reception amplifying unit 22 is frequency-shifted in the direction opposite to the frequency shift at the time of transmission based on the reception frequency hopping pattern signal FHPr, A receiving-side frequency shift circuit 23 for generating IFr, a data demodulating circuit 24 for demodulating the received intermediate frequency signal IFr and outputting demodulated data DMD, and an error for performing error correction processing on the demodulated data DMD and reproducing data. A correction circuit 26, and amplifies data from the error correction circuit 26 to output data DTo.
And an output circuit 27 that outputs a reception frequency hopping pattern signal FHPr to control the processing operation of the reception-side frequency shift circuit 23 and to control the processing operations of the data demodulation circuit 24 and the error correction circuit 26. And a portion 28x.

FIG. 5 shows an example of a frequency hopping pattern used between the transmitter 10x and the receiver 20x and an example of data to be transmitted. The frequency hopping pattern of this example has eight frequencies that can be obtained by hopping from f1 to f8. The cycle of one hopping pattern is obtained by dividing (hopping pattern cycle Thp) into eight sections and dividing these eight sections by time. When the sequential numbers (hereinafter referred to as hopping numbers) with the passage of t are given as H1, H2,..., H8, the hopping numbers H1, H2,.
In the order of H8 (that is, with time), the frequency is f2,
The pattern is shifted to f4, f6, f8, f1, f3, f5, f7. Then, data to be transmitted, for example, “Iroha...” Are sequentially allocated to the hopping numbers H1, H2,.

In this case, for example, even if there is interference or interference at the frequency f3 and the data (he, ga) at that portion is not transmitted to the receiver 20x or is erroneously transmitted, the surrounding data is transmitted normally. If so, the entire data can be reproduced by the error correction circuit 26. In this example, an example has been described in which one data is allocated to one transmission period using one frequency and data is transmitted. However, in order to more reliably reproduce data, one data is transmitted by hopping to a plurality of frequencies. In some cases, a high-speed FH method is used. However, there is a limit to the switching speed in order to transmit data normally by switching the frequency, and it is not suitable for data transmission with a high data transfer speed. When the data transfer speed is high or when the data transfer speed is increased, it is necessary to allocate and transmit a plurality of continuous data during one transmission period using one frequency.

[0006]

In the above-described conventional frequency hopping transmission system, in order to transmit data normally by frequency hopping, data transmission with a high data transfer rate is required because the frequency switching speed is limited. Is performed, it is necessary to allocate and transmit a plurality of continuous data during one transmission period using one frequency.
As shown in FIG. 6, if the data of the frequency f3 is not transmitted to the receiver 20x side or is erroneously transmitted due to interference or interference, a plurality of consecutive data ("Naramu" in the example of FIG. 6). ) Of data, the data of that part cannot be reproduced beyond the limit of the error correction function,
There is a problem that correct information cannot be transmitted.

An object of the present invention is to improve the reproducibility of data when there is interference or interference when the data transfer speed is high or when it is desired to increase the data transfer speed. An object of the present invention is to provide a frequency hopping transmission system capable of transmitting information accurately.

[0008]

SUMMARY OF THE INVENTION A frequency hopping transmission system for transmitting data by sequentially shifting the frequency of a signal to be transmitted to a plurality of different hopping frequencies in accordance with a predetermined hopping pattern. A system has the following configuration to achieve the above object. (A) an error correction control processing unit for performing predetermined transmission side error correction control processing on an input data sequence and outputting the same, and an order of the data sequence output from the error correction control processing unit, A data sequence rearrangement circuit that rearranges and outputs the same number of continuous data as the number of the different hopping frequencies in the column so as to be distributed to different hopping frequencies, and modulates the output data of the data sequence rearrangement circuit. A data modulation circuit for generating a transmitted transmission intermediate frequency signal, and a frequency hopping signal generated by sequentially shifting the frequency of the transmission intermediate frequency signal to the plurality of hopping frequencies according to the hopping pattern, and transmitting the generated signal to a data transmission path. A transmitter including: a frequency hopping signal generation / transmission unit; (b) frequency hopping transmitted through the data transmission path A reception amplification unit that receives a signal, amplifies and outputs the signal,
A reception-side frequency shift circuit that generates a reception intermediate frequency signal by shifting the frequency of the output signal of the reception amplification unit in a direction opposite to the frequency shift by the frequency hopping signal generation and transmission unit of the transmitter, A data demodulation circuit that demodulates the received intermediate frequency signal and outputs demodulated data, and reorders the order of the sequence of the demodulated data in a direction opposite to the data sequence recombination performed by the data sequence reordering circuit of the transmitter. A data string order restoration circuit that restores and outputs the data string order before data string recombination by the data string order recombination circuit, and an error correction circuit that performs error correction processing on output data of the data string order restoration circuit. , Including receiver

[0009] Further, a frequency hopping signal generation / transmission unit of the transmitter is a circuit for shifting the frequency of the transmission intermediate frequency signal to M different hopping frequencies, and during one transmission period at one hopping frequency, In the case of a system having a data transfer rate of transmitting N consecutive (N is plural) data included in the transmission intermediate frequency signal, the data sequence rearrangement circuit of the transmitter transmits M input data sequences. The data is sequentially divided into groups of data, and the divided N groups are regarded as one unit of data string order recombination. One data is taken from each of the N groups of one unit, in a predetermined group order, and It has a configuration that is a circuit that is sequentially taken out and arranged in a predetermined group order and used as a data string after the order rearrangement.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In one embodiment of the present invention, on the transmitter side, the order of data strings entering a data modulation circuit is determined by
A data sequence rearrangement circuit for rearranging the data sequence such that the same number of continuous data as the number of hopping frequencies used in the system is distributed to different hopping frequencies is provided. The sequence of the data sequence demodulated in the above is provided with a data sequence reconstructing circuit that recombines in the opposite direction to the transmitter side and restores the same sequence as the data sequence before recombination on the transmitter side. I have. With such a configuration, the data transfer rate is high, and in order to increase the data transfer rate, when a plurality of data are transmitted during one transmission period with one hopping frequency, a certain hopping frequency is used. If the data is lost due to interference or interference, the missing data will be distributed evenly in the data stream when the receiver restores the data stream order. The missing data can be reproduced by the error correction circuit, and the information can be transmitted accurately.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. 1A and 1B are block diagrams of a transmitter and a receiver showing one embodiment of the present invention. This embodiment is different from the conventional frequency hopping transmission system shown in FIGS. 4A and 4B in that an error correction control processing unit 12 and a data modulation circuit 14 are provided for a conventional transmitter 10x.
The order of the data sequence output from the error correction control processing unit 12 is changed so that the same number of continuous data of this data sequence as the number of hopping frequencies in the system is distributed to different hopping frequencies. A data sequence recombining circuit 13 for recombining and outputting to the data modulation circuit is provided, and a processing operation control function of the data sequence recombining circuit 13 is added to the transmission control unit 18x (the transmission control unit after adding this function). Is 18) the transmitter 10 and the conventional receiver 20
x, its data demodulation circuit 24 and error correction circuit 26
Between the data sequence output from the data demodulation circuit 24 and the data sequence rearrangement performed by the data sequence rearrangement circuit 13 of the transmitter 10 in the reverse direction. A data sequence reconstructing circuit 25 for reconstructing the data sequence before recombining the data sequence by the circuit 13 and outputting the reconstructed data sequence to the error correction circuit 26 is provided, and receives the processing operation control function of the data sequence reconstructing circuit 25. The receiver 20 is added to the control unit 28x (the reception control unit after this function is added is 28).
It is in the point which was.

Next, the data sequence reordering circuit 13
The operation of reordering the data strings will be specifically described with reference to FIG. First, the error correction control processing unit 12
, And the sequence thereof is “Iroha Niho Nito ...”, and it is assumed that the system has a data transfer rate of transmitting four data strings in one transmission at one hopping frequency (1HF). . In this case, the data sequence rearrangement circuit 13 sequentially divides the data sequence before recombination into groups of eight data (8 is the number of hopping frequencies) (group A, group B,...). Four divided groups (4 is the number of data transmitted in one transmission by one HF as described above) are defined as one unit of data sequence rearrangement, and the four groups of one unit (group A to group D) In order of one data from each, a predetermined group order (in the example of FIG. 2, groups A, B,
C, D, hereafter the order of repetition), the data order within the group (in the example of FIG. 2, the arrangement order within each group, that is, in the group A, the order of “i, ro, ha,...”). They are sequentially taken out and arranged, and output as a data sequence "Ireperonu Haruharu ..." after rearranging the order. By rearranging in this way, no matter how the hopping pattern (FHPt) in the transmission-side frequency shift circuit 15 changes,
Eight consecutive data in the data sequence before recombination are always assigned to different hopping frequencies.

FIG. 3 shows a case where the hopping frequency f3 of the frequency hopping signal transmitted from the transmitter 10 is disturbed and interfered with, and the receiver 20 receives the data when the hopping frequency f3 is lost due to interference. FIG. 7 is a diagram for explaining what state the data sequence after restoring the sequence of the data sequence will be. The data sequence demodulated by the data demodulation circuit 24 is "Ireperonu Haruru ...", and the data "Hekarama" transmitted at the hopping frequency f3 of this data sequence.
Is missing. When this data string is rearranged by the data string order restoration circuit 25 and returned to the original order, the missing data “he”, “ka”,
Since "ra" and "ma" are evenly distributed in the restored data string, the data in the missing portion can be easily reproduced by the error correction circuit, and the information can be transmitted accurately.

In this embodiment, when one data is allocated to one transmission period using one frequency, the order of the data sequence is changed by the transmission-side frequency shift circuit 1.
Since the result is the same as changing the order of the frequencies according to the frequency hopping pattern according to No. 5, it is the same as simply changing the hopping pattern to another pattern.

That is, according to the present invention, when a plurality of data must be transmitted during one transmission period of one hopping frequency due to a high data transfer rate, even if a certain frequency is subject to interference or interference, information is transmitted. Can be transmitted accurately,
Also, by transmitting a plurality of data during one transmission period of one hopping frequency, it is possible to increase the data transfer speed while accurately transmitting information even if there is interference or interference.

[0016]

As described above, according to the present invention, on the transmitter side, the order of the input data sequence is determined so that the same number of consecutive data of this data sequence as the number of hopping frequencies used in the present system are determined. Since the data is rearranged so as to be distributed to different hopping frequencies and then sent out as a frequency hopping signal, and the receiver has a function to restore the order of the sent data sequence, the data transfer speed is high. In the case where it is necessary to transmit a plurality of data during one transmission period of one hopping frequency, even if a certain hopping frequency is disturbed or interfered, the data of that part is uniformly distributed to the data sequence whose order is restored. Since the data can be dispersed, the reproducibility of the data is improved and the information can be transmitted accurately, and a plurality of data can be transmitted during one transmission period of one hopping frequency. So as to, it is possible to increase the data transfer rate while accurately transmitting even information if there is interference or interference, there is an effect that.

[Brief description of the drawings]

FIG. 1 is a block diagram of a transmitter and a receiver showing one embodiment of the present invention.

FIG. 2 is a diagram for explaining a specific operation of rearranging the data sequence on the transmitter side in the embodiment shown in FIG. 1;

FIG. 3 is a diagram for explaining data sequence order restoration and its effect on the receiver side in the embodiment shown in FIG. 1;

FIG. 4 is a block diagram of a transmitter and a receiver as an example of a conventional frequency hopping transmission system.

5 is a diagram illustrating an example of a frequency hopping pattern in the frequency hopping transmission system illustrated in FIG. 4 and distribution of data with respect to hopping frequencies.

6 is a diagram for explaining a problem in the frequency hopping transmission system shown in FIG.

[Explanation of symbols]

 10, 10x transmitter 11 input circuit 12 error correction control processing unit 13 data sequence rearrangement circuit 14 data modulation circuit 15 transmission side frequency shift circuit 16 signal transmission unit 18, 18x transmission control unit 20, 20x receiver 22 reception amplification Unit 23 reception-side frequency shift circuit 24 data demodulation circuit 25 data string order restoration circuit 26 error correction circuit 27 output circuit 28, 28x reception control unit

Claims (2)

[Claims] 1. A frequency hopping transmission system for transmitting data by sequentially shifting the frequency of a signal to be transmitted to a plurality of different hopping frequencies according to a predetermined hopping pattern, comprising: Characteristic frequency hopping transmission system. (A) an error correction control processing unit for performing predetermined transmission side error correction control processing on an input data sequence and outputting the same, and an order of the data sequence output from the error correction control processing unit, A data sequence rearrangement circuit that rearranges and outputs the same number of continuous data as the number of the different hopping frequencies in the column so as to be distributed to different hopping frequencies, and modulates the output data of the data sequence rearrangement circuit. A data modulation circuit for generating a transmitted transmission intermediate frequency signal, and a frequency hopping signal generated by sequentially shifting the frequency of the transmission intermediate frequency signal to the plurality of hopping frequencies according to the hopping pattern, and transmitting the generated signal to a data transmission path. A transmitter including: a frequency hopping signal generation / transmission unit; (b) frequency hopping transmitted through the data transmission path A reception amplification unit that receives a signal, amplifies and outputs the signal,
A reception-side frequency shift circuit that generates a reception intermediate frequency signal by shifting the frequency of the output signal of the reception amplification unit in a direction opposite to the frequency shift by the frequency hopping signal generation and transmission unit of the transmitter, A data demodulation circuit that demodulates the received intermediate frequency signal and outputs demodulated data, and reorders the order of the sequence of the demodulated data in a direction opposite to the data sequence recombination performed by the data sequence reordering circuit of the transmitter. A data string order restoration circuit that restores and outputs the data string order before data string recombination by the data string order recombination circuit, and an error correction circuit that performs error correction processing on output data of the data string order restoration circuit. , Including receiver 2. A circuit, wherein a frequency hopping signal generation and transmission section of the transmitter shifts the frequency of the transmission intermediate frequency signal to M different hopping frequencies.
In the case of a system having a data transfer rate of transmitting N consecutive (N is plural) data included in the transmission intermediate frequency signal during one transmission period using the hopping frequency,
The data sequence rearrangement circuit of the transmitter sequentially divides the input data sequence into M data groups, and uses the divided N units as one unit of the data sequence rearrangement, the one unit N 2. A frequency circuit according to claim 1, wherein said data is a circuit which sequentially takes out and arranges one data at a time in a predetermined group order and an order within a predetermined group one by one from each of said groups to form a data string after the order rearrangement. Hopping transmission system.