CN107528611B

CN107528611B - Odd number user L-G model synchronous orthogonal frequency hopping radio station sorting method

Info

Publication number: CN107528611B
Application number: CN201710756622.0A
Authority: CN
Inventors: 金玮萱; 廖红舒; 甘露
Original assignee: University of Electronic Science and Technology of China
Current assignee: University of Electronic Science and Technology of China
Priority date: 2017-08-29
Filing date: 2017-08-29
Publication date: 2020-03-31
Anticipated expiration: 2037-08-29
Also published as: CN107528611A

Abstract

The invention belongs to the field of communication countermeasure, and particularly relates to odd-number user synchronous orthogonal frequency hopping signal sorting under the condition of an optimal frequency modulation sequence family constructed by an L-G model. A method for sorting odd number of user L-G model synchronous orthogonal frequency hopping radio stations comprises the steps of mapping a received frequency set into a binary sequence, establishing a standard according to the result of mutual exclusive OR of sequence values at a first moment, comparing the exclusive OR result of different address codes with that of all address codes at each moment subsequently received with the standard, and sorting. For the L-G model to generate the frequency hopping sequence set, when the number of users is an odd number, direction finding and network information parameter measurement are not needed, sorting can be performed only through the sequence values, and the method is simple and easy to implement.

Description

Odd number user L-G model synchronous orthogonal frequency hopping radio station sorting method

Technical Field

The invention belongs to the field of communication countermeasure, and particularly relates to odd-number user synchronous orthogonal frequency hopping signal sorting under the condition of an optimal frequency modulation sequence family constructed by an L-G model.

Background

In recent years, frequency hopping communication has been widely applied and greatly developed in the field of military communication due to its strong anti-interference and networking application capabilities and low interception characteristics. Therefore, the research on the frequency hopping communication networking and the network station sorting method thereof has very important significance in the field of communication countermeasure. On one hand, as a countermeasure, the networking mode of various frequency hopping communication radio stations needs to be fully researched, and the principle of the whole communication process is well known, so that the communication of an enemy is conveniently tracked, and enemy information is obtained; on the other hand, the deep research on the sorting method of the frequency hopping network station is beneficial to perfecting the military communication of the frequency hopping network station and protecting the communication safety of the own frequency hopping network station.

When a plurality of frequency hopping radio stations perform synchronous networking, an optimal frequency hopping sequence family constructed by using an L-G model is used, and the construction method is as shown in FIG. 1. The L-G model is constructed based on n-stage m sequence generator in finite field GF (2), and after the outputs of r (r is not more than n) registers (adjacent or non-adjacent stages) and r user address code are added modulo-2, the frequency synthesizer is controlled. The tap output of the shift register at the same time is j₀…j_r-1Using different address codes v for different stations₀…v_r-1The output of the tap is bitwise xored with the address code to obtain Sv and control the frequency synthesis, the frequency mapping is shown in fig. 2, taking an 8-bit address code as an example. Different network stations use different address codesThe output of the register which is the same as the output of the m sequence generator is modulo two and then controls the frequency synthesizer, so that the frequency does not collide in the communication process. The frequency hopping frequency set, the frequency hopping rate and the hopping time of the networking radio station are the same, namely the networking radio station is called a synchronous orthogonal network station. The existing common method mainly carries out sorting according to the difference of synchronous frequency, the difference of network information parameters and the difference of DOA, but the network establishment process of the frequency hopping network station is short and is not easy to detect, and the network information parameters are difficult to obtain by non-cooperative parties; the frequency and the direction angle are easily affected by the electromagnetic environment, and the direction angle is complicated to measure in practical cases. It is therefore necessary to develop a simple resolution.

Disclosure of Invention

The invention aims to solve the technical problem of distinguishing which net station each frequency value in a frequency set arriving at the same time belongs to. For the hopping sequence family generated by the L-G model, because each network station frequency is determined by the xor of the address code and the tap output of the shift register, the tap output of the shift register is the same at the same time, and each network station address code is fixed and different (for example, one user address code in 4-bit address codes is 0010), the xor result of the hopping sequence values of different network stations is equal to the xor result of the corresponding address codes. Mapping the received frequency set into a binary sequence, establishing a standard according to the mutual exclusive or result of the sequence value at the first moment, and comparing the frequency exclusive or value at each subsequent received moment with the standard and sorting the frequency exclusive or values because the exclusive or results of different address codes and all address codes are different.

A method for sorting odd-number user L-G model synchronous orthogonal frequency hopping radio stations comprises the following specific steps:

s1, mapping the received frequency points to binary sequences, as shown in fig. 3;

s2, counting the received frequency point set as N moments, wherein m are odd numbers, and m users at each moment are represented as 1-m, represented by T1-TN, and initialized to E [ ] for storing sorting results;

s3, recording the time T1 as U ═ U in the binary sequence set₁,u₂…u_m]Wherein u is₁～u_mRespectively mapping frequency points received by m users at T1 momentShooting the result of the binary sequence, and storing the result into E (: 1) ═ U;

s4, carrying out bitwise XOR operation on each sequence value in the binary sequence set U and all sequence values in the binary sequence set U in the S3, and storing the result into a matrix

The first column of the matrix is the exclusive or result of the sequence value of the user 1 and all the sequence values at the time of T1, which is recorded as S1, the second column of the matrix is the exclusive or result of the sequence value of the user 2 and all the sequence values at the time of T1, which is recorded as S2, and the mth column of the matrix is the exclusive or result of the sequence value of the user m and all the sequence values at the time of T1, which is recorded as Sm;

s5, if the number of time cycles is N, the binary sequence set at the time Tq is fq ═ f₁,f₂…f_m]Wherein q is 2;

s6, setting the circulation times of the user as m, and calculating f_iExclusive OR with all f

Wherein i is 1;

s7, comparing the T in the S6 with the Sk column in the S4, if the T column in the S6 is the same as the Sk column in the S4, judging the frequency f_iBelongs to the kth net station, will f_iStoring fq' (k) ═ f_iWherein, k is 1,2, 3.

S8, if i is less than m, making i equal to i +1, and returning to S5;

and S9, judging that E (: q) ═ fq', if q is less than N, making q ═ q +1, returning to S6, and otherwise, finishing the cycle and finishing the sorting by one user frequency point sequence of each line in E.

The invention has the beneficial effects that:

for the L-G model to generate the frequency hopping sequence set, when the number of users is an odd number, direction finding and network information parameter measurement are not needed, sorting can be performed only through the sequence values, and the method is simple and easy to implement.

Drawings

Fig. 1 constructs a hopping sequence for an L-G model.

Fig. 2 is a frequency map of sequence mapping.

Fig. 3 is a binary sequence diagram of frequency point reverse mapping.

FIG. 4 is a flow chart of the method of the present invention.

Detailed Description

The present invention will be described with reference to the accompanying drawings.

In the invention, 5 user frequency point sets are sorted at 4 receiving moments, and each user address code has 4 bits:

the detection implementation method of the embodiment is shown in FIG. 4.

Consider the L-G tap sequence four times j ═ 0001011000101101]Address code v ═ 00000001011010011100]Frequency hopping sequence

The method comprises the following steps:

the method comprises the following steps: the received set of frequencies is mapped to a binary sequence.

Step two: and counting the received frequency point set to be 4 moments, each moment is 5 users, and m is an odd number.

Step three: the binary sequence set at time T1 is U ═ 00000001011110001101, and stored as E (: 1) ═ U.

Step four: and storing the result of bitwise XOR between each frequency value in the U and all frequency values in the U into S, wherein the first column of the matrix is the result of XOR between the sequence value of the user 1 and all sequence values at the time of T1 and is marked as S1, and each column is arranged from small to large.

Step five: the binary sequence set at time T2 is f2 ═ 00000110011110101111.

Step six: i is 1, T00000110011110101111 is S3, so 0000 belongs to S3 corresponding user, and f 2' (3) is 0000.

Step seven: since i is 2 and T is 00000001011010011100 is S2, 0110 belongs to S2 and f 2' (2) is 0110.

Step eight: since i is 3 and T is 00000001011110001101 is S1, 0111 belongs to S1 and f 2' (1) is 0111.

Step nine: i is 4, T00000101101011001101 is S5, so 1010 belongs to S5 and f 2' (5) is 1010.

Step ten: since i is 5 and T is 00000101100010011111 is S4, 1111 belongs to S4 corresponding users, and f 2' (4) is 1111.

Step eleven: that is, at time T2, f2 'is [ 01110110000011111010 ], and E (: 2) is f 2'.

Step twelve: the binary sequence set at time T3 is f3 ═ 00100011010010111110

Step thirteen: a similar process from step five to step nine is repeated for the binary sequence set f3, i.e., T3 is written with f3 ═ 00110010010010111110, and E (: 3) ═ f 3'.

Fourteen steps: the binary sequence set at time T4 is f4 ═ 00010100101111001101.

Step fifteen: a similar process from step five to step nine is repeated for the binary sequence set f4, i.e., T4 at time f4 ═ 11001101101101000001, and E (: 4) ═ f 4' is stored.

Sixthly, the steps are as follows: namely, 4 time frequency values of five users are obtained

The binary sequences corresponding to the time frequencies of the first user T1-T4 are as follows in sequence: 0000011100111100,

the binary sequences corresponding to the time frequencies of the second user T1-T4 are as follows in sequence: 0001011000101101,

the binary sequences corresponding to the time frequencies of the third user T1-T4 are as follows in sequence: 0111000001001011,

the binary sequences corresponding to the time frequencies of the fourth user T1-T4 are as follows in sequence: 1000111110110100,

the binary sequences corresponding to the time frequencies of the fifth user T1-T4 are as follows in sequence: 1101101011100001.

Claims

1. a method for sorting odd-number user L-G model synchronous orthogonal frequency hopping radio stations is characterized by comprising the following specific steps:

s1, mapping the received frequency points into binary sequences;

s2, counting N moments of a received frequency point set, wherein the N moments are represented by T1-TN, m users at each moment are represented by 1-m, m is an odd number, and E [ ] is initialized to store sorting results;

s3, recording the time T1 as U ═ U in the binary sequence set₁,u₂…u_m]Wherein u is₁～u_mRespectively mapping frequency points received by m users at the time of T1 into a binary sequence result, and storing the result into E (: 1) ═ U;

The first column of the matrix is the exclusive or result of the sequence value of the user 1 and all the sequence values at the time of T1, which is recorded as S1, each column is arranged from small to large, the second column of the matrix is the exclusive or result of the sequence value of the user 2 and all the sequence values at the time of T1, which is recorded as S2, and the mth column of the matrix is the exclusive or result of the sequence value of the user m and all the sequence values at the time of T1, which is recorded as Sm;

s5, setting the time cycle number as N, setting the user cycle number as m, and setting the initialization q as 2 and i as 1;

s6, the binary sequence set at the Tq moment is f_q＝[f₁,f₂…f_m]；

S7, calculating the exclusive or of fi and all f

S8, comparing the T in S7 with the Sk in S4, if the T in S7 is the same as the Sk-th row in S4, judging the frequency f_iBelongs to the kth net station, will f_iStoring fq' (k) ═ f_iWherein, k is 1,2, 3.

S9, if i is less than m, making i equal to i +1, and returning to S7;

and S10, judging that E (: q) ═ fq', if q is less than N, making q ═ q +1, returning to S6, and otherwise, finishing the cycle and finishing the sorting by one user frequency point sequence of each line in E.