CN102984810A - Centralized-control-free satellite information channel dynamic access method - Google Patents

Abstract

The invention discloses a centralized-control-free satellite information channel dynamic access method. The method comprises the following steps: S1: a user starts the business communication and sets communications parameters which comprise business types and communication bandwidths; S2: the user judges if a satellite terminal is connected with a corresponding end through an information channel, the width of the information channel is greater than or equal to that of an application bandwidth, and if the width of the information channel is greater than or equal to that of the application bandwidth, then here is S6, and if not, here is S3; S3: a satellite earth station adopts a spectrum sensing method based on cognition to detect usable information channels; S4: the earth station judges the detected usable information channels; and S5: the detected usable information channels are ranked according to information channel numbers, like x0, x1, x2...x m,...x n, and a median information channel x m after being ranked is determined. The centralized-control-free satellite information channel dynamic access method not only improves spectral using rate, but also improves system availability under an emergency condition.

Description

A kind of satellite channel dynamic access method of no center control

Technical field

The present invention relates to the Satellite communication access control field, particularly a kind of satellite communication channel dynamic access method of no center control.

Background technology

Along with the development of satellite platform and load technology, the usable satellite bandwidth is more and more wider, and owing to reasons such as rate, causes that satellite user is relatively rare, the satellite frequency spectrum utilance is lower.On the other hand, traditional satellite communication resource is distributed the general centralized control method of salary distribution that adopts, namely applied for and present satellite resource operating position allocated channel according to earth station is professional by network control center station, and owing to reasons such as natural disaster or bad weathers, in case the network control center breaks down at the station, will cause the total system paralysis.Therefore, set up a kind of central controlled autonomous dynamic access method of central station that do not rely on, not only can provide the satellite frequency spectrum utilance, and can improve the reliability of system under emergent emergency case, it is necessary just to seem.

Summary of the invention

Technical problem: technical problem to be solved by this invention provides a kind of satellite channel dynamic access method of no center control, each terminal use adopts cognitive method independently to detect current available satellite channel situation, and the autonomous tuning algorithm by no center control, set up dynamically mutual annexation.

Technical scheme: for solving the problems of the technologies described above, the invention provides a kind of satellite channel dynamic access method of no center control, the method may further comprise the steps:

Step 1: the user initiates this service communication, and messaging parameter is set, and messaging parameter comprises type of service, communication bandwidth;

Step 2: ICBM SHF satellite terminal judges whether with the built vertical connecting channel in opposite end and channel width if then turn step 6, otherwise to turn step 3 more than or equal to bandwidth application;

Step 3: satellite earth station adopts the frequency spectrum sensing method based on cognition to detect available channel;

Step 4: earth station is judged the available channel that detects, if available channel bandwidth is applied for communication bandwidth less than the user, then is handled as follows:

Step 41: whether judge this business to the sensitivity of delaying time, if delay time then prompting user communication failure of sensitive kinds business, turn step 8;

Step 42: calculate remaining bandwidth=bandwidth application-available bandwidth, the buffer memory business datum turns step 6 to next sense cycle;

Step 5: to the channel that detects according to the channel number x that sorts ₀, x ₁, x ₂... x _m... x _n

And the median channel x after determining to sort _m

Step 6: send beacon signal at the median channel, and the wait opposite end is replied;

Step 7: reply if receive the opposite end, then both sides enter communication, if do not receive and reply, can think median channel x _mIn range of channels is detected in the opposite end, then in the available channel sequence, do not remove x _m, and turn step 5, if still can't connect in maximum delay, then the prompting user communication failure turns step 8;

Step 8: sign off, communicating pair discharges satellite channel resource.

Preferably, the Channel Detection algorithm in the step 3 adopts based on the relevant frequency spectrum sensing method of spectrum as follows:

Step 31: calculate Spectral correlation function;

$S_x^{\mathrm{\α}}\left(f\right)=\frac{1}{\mathrm{NT}}\underset{n=0}{\overset{N}{\∑}}X(n,f+\mathrm{\α}/2)X^{*}(n,f-\mathrm{\α}/2)$

Wherein,

Spectral correlation function for signal; α is cycle frequency; F is channel to be detected; N sample data is divided into the data block of every group of T sample, and n is sampling number; N is the sampling sum; T is each sample number; X (n, f) is the fast fourier transform of the sample number of the n time sampling;

Step 32: calculate spectral correlative coefficient;

$C_x^{\mathrm{\α}}\left(f\right)=\frac{S_x^{\mathrm{\α}}\left(f\right)}{{\left[S_x^0(f+\mathrm{\α}/2)S_x^0(f-\mathrm{\α}/2)\right]}^{1/2}}$

Wherein,

Spectral correlative coefficient for signal; α is cycle frequency; F is channel to be detected;

Spectral correlation function for signal;

Spectral correlation function for α=0 o'clock; Step 33: judge whether channel is occupied: if

Then channel is unoccupied, otherwise channel is occupied, and η is predefined decision threshold here; Record unoccupied channel number.

Preferably, in step 7, after communicating pair entered communication, it was as follows to increase the control step: communicating pair continues to detect the use channel and the primary user whether occurs; In case the primary user occurs, communicating pair should discharge immediately satellite channel and re-start connection.

Preferably, after communicating pair connected, both sides discharged the backup channel sequence that reconnects behind the channel at first alternately in step 7; In case the primary user occurs, and carries out according to the reserve sequence order when then both sides reconnect.

Beneficial effect: the present invention provides a kind of satellite channel dynamic access method of new no center control, and by the method, satellite communication earth station adopts frequency spectrum sensing method, autonomous detection usable satellite channel, and according to median rules selection communication channel; After authorized master user occurs, discharge immediately channel and rebulid connection according to predefined reserve Selective sequence.Because this method earth station uses cognitive method dynamic access satellite channel, compare with traditional centralized control method and need not to arrange control channel, therefore earth station also need not to dispose control channel, has not only improved the availability of frequency spectrum but also has reduced the cost of channel terminal; On the other hand, this method need not network control center's station equipment, has therefore reduced the system Construction cost, and has improved system availability under emergent emergency case.

Description of drawings

Fig. 1 is earth station dynamic access satellite channel flow chart;

Fig. 2 is earth station handshake procedure schematic diagram;

Fig. 3 earth station uses the reserve sequence to reconnect the process schematic diagram;

Fig. 4 communication process schematic diagram.

Embodiment

Below in conjunction with accompanying drawing, the present invention will be further described.

Referring to Fig. 1-4, the satellite channel dynamic access method of no center control provided by the invention, the method may further comprise the steps:

1) user initiates this service communication, and messaging parameter (type of service, communication bandwidth etc.) is set;

2) ICBM SHF satellite terminal judges whether with the built vertical connecting channel in opposite end and channel width if then turn step 6, otherwise to turn step 3 more than or equal to bandwidth application;

3) satellite earth station adopts the frequency spectrum sensing method based on cognition to detect available channel;

4) earth station is judged the available channel that detects, if available channel bandwidth is applied for communication bandwidth less than the user, then is handled as follows:

(a) whether judge this business to the sensitivity of delaying time, if delay time then prompting user communication failure of sensitive kinds business, turn step 8;

(b) calculate remaining bandwidth=bandwidth application-available bandwidth, the buffer memory business datum turns step 6 to next sense cycle;

5) to the channel that detects according to the channel number x that sorts ₀, x ₁, x ₂... x _m... x _nAnd the median channel x after determining to sort _m

6) send beacon signal at the median channel, and the wait opposite end is replied;

7) if receiving the opposite end replys, then both sides enter communication, if do not receive and reply, then remove x in the available channel sequence _m, and turn step 5, if still can't connect in maximum delay, then the prompting user communication failure turns step 8;

8) sign off, communicating pair discharges satellite channel resource.

Channel Detection algorithm in the step 3 adopts based on the relevant frequency spectrum sensing method of spectrum, specifically is calculated as follows:

(a) calculate Spectral correlation function

$S_x^{\mathrm{\α}}\left(f\right)=\frac{1}{\mathrm{NT}}\underset{n=0}{\overset{N}{\∑}}X(n,f+\mathrm{\α}/2)X^{*}(n,f-\mathrm{\α}/2)$

Wherein,

Spectral correlation function for signal; α is cycle frequency; F is channel to be detected; N sample data is divided into the data block of every group of T sample, and n is sampling number; N is the sampling sum; T is each sample number; X (n, f) is the fast fourier transform of the sample number of the n time sampling;

(b) calculate spectral correlative coefficient

$C_x^{\mathrm{\α}}\left(f\right)=\frac{S_x^{\mathrm{\α}}\left(f\right)}{{\left[S_x^0(f+\mathrm{\α}/2)S_x^0(f-\mathrm{\α}/2)\right]}^{1/2}}$

Wherein,

Spectral correlative coefficient for signal; α is cycle frequency; F is channel to be detected;

Spectral correlation function for signal;

Spectral correlation function for α=0 o'clock;

(c) judge whether channel is occupied: if

Then channel is unoccupied, and is no

Then channel is occupied, and η is predefined decision threshold here.Record unoccupied channel number.

In step 7, for avoiding interference primary user's communication, must discharge immediately channel, re-start channel access.For this reason, after communicating pair entered communication, it was as follows to increase the control step in step 7: communicating pair continues to detect the use channel and the primary user whether occurs.In case the primary user occurs, communicating pair should discharge immediately satellite channel and re-start connection.

Again the time-delay that accesses in order to reduce communicating pair, can adopt following method: after communicating pair connected, both sides discharged the backup channel sequence that reconnects behind the channel at first alternately, such as x in step 7 ₃, x ₄, x ₇...; In case the primary user occurs, and carries out according to the reserve sequence order when then both sides reconnect.

The above only is preferred embodiments of the present invention; protection scope of the present invention is not limited with above-mentioned execution mode; as long as the equivalence that those of ordinary skills do according to disclosed content is modified or changed, all should include in the protection range of putting down in writing in claims.

Claims (4)

1. the satellite channel dynamic access method of a no center control is characterized in that the method may further comprise the steps:

Step 1: the user initiates this service communication, and messaging parameter is set, and messaging parameter comprises type of service, communication bandwidth;

Step 2: ICBM SHF satellite terminal judges whether with the built vertical connecting channel in opposite end and channel width if then turn step 6, otherwise to turn step 3 more than or equal to bandwidth application;

Step 3: satellite earth station adopts the frequency spectrum sensing method based on cognition to detect available channel;

Step 4: earth station is judged the available channel that detects, if available channel bandwidth is applied for communication bandwidth less than the user, then is handled as follows:

Step 41: whether judge this business to the sensitivity of delaying time, if delay time then prompting user communication failure of sensitive kinds business, turn step 8;

Step 42: calculate remaining bandwidth=bandwidth application-available bandwidth, the buffer memory business datum turns step 6 to next sense cycle;

Step 5: to the channel that detects according to the channel number x that sorts ₀, x ₁, x ₂... x _m... x _nAnd the median channel x after determining to sort _m

Step 6: send beacon signal at the median channel, and the wait opposite end is replied;

Step 7: reply if receive the opposite end, then both sides enter communication, if do not receive and reply, can think median channel x _mIn range of channels is detected in the opposite end, then in the available channel sequence, do not remove x _m, and turn step 5, if still can't connect in maximum delay, then the prompting user communication failure turns step 8;

Step 8: sign off, communicating pair discharges satellite channel resource.

2. the satellite channel dynamic access method of no center control according to claim 1 is characterized in that: the Channel Detection algorithm in the step 3 adopts based on the relevant frequency spectrum sensing method of spectrum as follows:

Step 31: calculate Spectral correlation function;

$S_x^{\mathrm{\α}}\left(f\right)=\frac{1}{\mathrm{NT}}\underset{n=0}{\overset{N}{\∑}}X(n,f+\mathrm{\α}/2)X^{*}(n,f-\mathrm{\α}/2)$

Wherein,

Spectral correlation function for signal; α is cycle frequency; F is channel to be detected; N sample data is divided into the data block of every group of T sample, and n is sampling number; N is the sampling sum; T is each sample number; X (n, f) is the fast fourier transform of the sample number of the n time sampling;

Step 32: calculate spectral correlative coefficient;

$C_x^{\mathrm{\α}}\left(f\right)=\frac{S_x^{\mathrm{\α}}\left(f\right)}{{\left[S_x^0(f+\mathrm{\α}/2)S_x^0(f-\mathrm{\α}/2)\right]}^{1/2}}$

Wherein,

Spectral correlative coefficient for signal; α is cycle frequency; F is channel to be detected; Spectral correlation function for signal;

Spectral correlation function for α=0 o'clock;

Step 33: judge whether channel is occupied: if

Then channel is unoccupied,

Otherwise channel is occupied, and η is predefined decision threshold here; Record unoccupied channel number.

3. the satellite channel dynamic access method of no center control according to claim 1 is characterized in that:

In step 7, after communicating pair entered communication, it was as follows to increase the control step: communicating pair continues to detect the use channel and the primary user whether occurs; In case the primary user occurs, communicating pair should discharge immediately satellite channel and re-start connection.

4. the satellite channel dynamic access method of no center control according to claim 3 is characterized in that:

After communicating pair connected, both sides discharged the backup channel sequence that reconnects behind the channel at first alternately in step 7; In case the primary user occurs, and carries out according to the reserve sequence order when then both sides reconnect.

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