CN101778435B - Method and device for allocating frequency spectrum resource in heterogeneous wireless network - Google Patents

Abstract

The present invention provides a method and device for allocating spectrum resources in a heterogeneous wireless network. The method and device belong to the field of network communication. Idle, if yes, then accept the request of the unlicensed user, and allocate the unlicensed user to the common frequency band; if not, when the reserved frequency band is free, receive the request of the unlicensed user, and allocate the Unauthorized users are allocated to reserved frequency bands; the common frequency bands are: frequency bands that provide services for authorized users and unlicensed users; the reserved frequency bands are: frequency bands that provide services exclusively for unlicensed users. The technical solution provided by the specific embodiment of the present invention has the advantage of ensuring the quality of service of the unauthorized user when the authorized user appears.

Description

A method and device for allocating spectrum resources in a heterogeneous wireless network

technical field

The present invention relates to the communication field, in particular to a method and device for allocating frequency spectrum resources in a heterogeneous wireless network.

Background technique

In recent years, from 3G to WLAN, WiMAX, from UWB to ZigBee, from Bluetooth to DVB-H, the diversified development pattern of wireless communication has become increasingly obvious, and the complementary integration of various wireless network technologies has become the general trend. The rapid development of wireless communication not only puts forward higher requirements for the organic integration of heterogeneous networks, but also puts forward higher requirements for spectrum resources. The existing wireless spectrum allocation system is fixed spectrum allocation, which divides the spectrum into two parts: licensed frequency band (Licensed Frequency Band, LFB) and unlicensed frequency band (Unlicensed Frequency Band, UFB). Most of the spectrum resources are used in licensed frequency bands, such as 3G, WiMAX, UWB, etc.; the spectrum resources in unlicensed frequency bands are much less. Due to the rapid development of wireless communication services such as WLAN, WPAN, and WMAN, the working of these networks Unlicensed frequency bands are approaching saturation.

The measurement results of spectrum resource utilization in recent years show that licensed users (LicensedUsers, LUs) actually make insufficient use of their licensed spectrum (less than 15%), and there are a large number of spectrum holes; compared with traditional fixed spectrum Compared with the allocation scheme, cognitive radio (CognitiveRadio, CR) technology introduces unlicensed users (Unlicensed Users, ULUs) in the licensed frequency band to opportunistically access the spectrum of the licensed network, which creates a new way to solve the shortage of spectrum resources and improve spectrum utilization. situation. In order to protect the communication quality of authorized users, the introduction of unauthorized users needs to meet a prerequisite, that is, its transmission must meet the interference temperature constraints of authorized users; in addition, when authorized users appear, unauthorized users should immediately return the current authorization Spectrum, turn to find other free frequency bands.

In the process of realizing the present invention, the inventor finds that the prior art has the following problems:

Since the technical solution in the prior art does not specifically reserve frequency bands for unlicensed users, this solution must affect the quality of service (Qos) of unlicensed users.

Contents of the invention

The specific embodiment of the present invention provides a method and device for allocating frequency spectrum resources in a wireless network. The method and device have the advantage of ensuring the service quality of unlicensed users.

The present invention provides a method for allocating spectrum resources in a heterogeneous wireless network, the method comprising:

After the network of the authorized frequency band receives the request of the unlicensed user, it is judged whether the common frequency band is idle, and if so, the request of the unlicensed user is accepted, and the unlicensed user is allocated to the common frequency band;

If not, when the reserved frequency band is free, the request of the unlicensed user is received, and the unlicensed user is allocated to the reserved frequency band;

The common frequency band is: a frequency band providing services for authorized users and unlicensed users; the reserved frequency band is: a frequency band exclusively providing services for unlicensed users.

The present invention provides a device for allocating spectrum resources in a heterogeneous wireless network, the device comprising:

The judging unit is used to judge whether the common frequency band is idle after receiving a request from an unlicensed user in the authorized frequency band network;

a common access unit, configured to accept the request of the unlicensed user and allocate the unlicensed user to a common frequency band when the judging unit judges yes;

The reserved access unit is configured to receive the request of the unlicensed user and allocate the unlicensed user to the reserved frequency band when the judgment unit judges no, when the reserved frequency band is idle;

The common frequency band is: a frequency band providing services for authorized users and unlicensed users; the reserved frequency band is: a frequency band exclusively providing services for unlicensed users.

The technical solution provided by the above specific embodiments of the present invention has the advantage of ensuring the service quality of unauthorized users even when authorized users appear.

Description of drawings

FIG. 1 is a flowchart of a method for allocating spectrum resources in a heterogeneous wireless network provided by the present invention;

FIG. 2 is a structural diagram of an apparatus for allocating spectrum resources in a heterogeneous wireless network according to the present invention.

Detailed ways

A specific embodiment of the present invention provides a method for allocating spectrum resources in a heterogeneous wireless network, as shown in FIG. 1 , including:

S11. After receiving the request from the unauthorized user, detect whether the common frequency band is idle, if so, proceed to step S12; otherwise proceed to S13-S15;

S12. Accept the request of the unlicensed user, and allocate the unlicensed user to a common frequency band;

S13. Detect whether the reserved frequency band is free, if so, proceed to S14; otherwise proceed to S15;

S14. Accept the request of the unlicensed user, and allocate the unlicensed user to the reserved frequency band;

S15. Reject the request of the unauthorized user.

In the method provided by the invention, the unlicensed users are assigned to the reserved frequency band under the condition that the common frequency band has no free channels, thereby ensuring the Qos of the unlicensed users.

The above method can be completed by the network in the licensed frequency band, for example; 3G, WiMAX, UWB, etc.

The common frequency band in the above method may be a frequency band providing services for authorized users and unlicensed users, and the reserved frequency band may be a frequency band exclusively providing services for unlicensed users.

Optionally, after S14, the above method may further include: if it is detected that the common frequency band is idle, switching the unlicensed user to the common frequency band. When the common frequency band is free, the unlicensed users are converted from the reserved frequency band to the common frequency band, increasing the number of channels in the reserved frequency band, so that the reserved frequency band can access more authorized users, further improving the unlicensed user’s Qos,

Optionally, the allocation method of the common frequency bands and reserved frequency bands above can be statically configured. Taking the 3G network as an example, 80% of the authorized frequency bands of the 3G network are allocated to the common frequency bands, and 20% of the authorized frequency bands of the 3G network are allocated to reserve frequency bands. Of course, the allocation method of the common frequency band and the reserved frequency band can be dynamically configured, that is, the number of channels in the reserved frequency band is calculated according to the interruption probability allowed by the authorized user; the specific calculation method can be:

表示信道K是否被占用，φ_k＝0表示信道K空闲，而φ_k＝1则表示信道K正在被使用。令(i，j，l)表示系统状态，其中i，j和l分别表示占用普通频段的非授权用户的个数，占用普通频段的授权用户的个数和占用预留频段的非授权用户的个数；系统的状态空间Δ＝{(i，j，l)|i+j≤J，l≤L}。令π(i，j，l)表示稳态概率分布，其中(i，j，l)∈Δ；For the convenience of calculation, the authorized frequency bands of the system are divided into the reserved frequency band set ￡ _R = {1, 2, ..., L} and the common frequency band set ￡ _N = {1, 2, ..., J}, Among them, L+J=K; L and J respectively represent the number of channels in the reserved frequency band and the number of channels in the common frequency band, and K represents the total number of channels in the authorized frequency band; the indicator vector

Indicates whether the channel K is occupied, φ _k =0 indicates that the channel K is idle, and φ _k =1 indicates that the channel K is being used. Let (i, j, l) represent the state of the system, where i, j and l respectively represent the number of unlicensed users occupying the common frequency band, the number of authorized users occupying the common frequency band and the number of unlicensed users occupying the reserved frequency band number; the state space of the system Δ={(i, j, l)|i+j≤J, l≤L}. Let π(i,j,l) denote the steady-state probability distribution, where (i,j,l)∈Δ;

When the channel resources are sufficient, that is, Δ ₁ ={(i, j, l)|i+j<J, l=0}, all new network users, no matter authorized users or unauthorized users, can be allocated to ordinary frequency band, so there will be no communication interruption, then the formula (1) can be expressed as:

[iμ _s +λ _s +(i+1)μ _p +λ _p ]π(i,j,l)

=λ _s π(i-1,j,0)+(i+1)μ _s π(i+1,j,0)

+λ _p π(i,j-1)+(i+1)μ _p π(i,j+1)(1)

Among them, μ _s represents the probability of service time of unauthorized user services; μ _p represents the probability of service time of authorized user services; λ _s represents the arrival probability of unauthorized users, and λ _p represents the arrival probability of authorized users.

When all common frequency bands in the system are occupied, and some reserved frequency bands are also used by unauthorized users, the state of the system at this time Δ ₂ ={(i,j,l)|i+j=J,l <L}; using formula (2) can be expressed as:

[λ _s +(j+l)μ _s +jμ _p +λ _p ]π(i,j,l)

=(i+j+1)μ _s π(i,j,l+1)+λ _s π(i,j,l-1)

+λ _p π(i+1,j-1,l-1)+(j+1)μ _p π(i-1,j+1,l+1)(2)

When all common frequency bands in the system are used by licensed users, and unlicensed users can only use reserved channels, the state of the system at this time Δ ₃ ={(i,j,l)|i=0,j=J,l <L}; using formula (3) can be expressed as:

[λ _s +lμ _s +Jμ _p ]π(0, J, l)

=(l+1)μ _s π(0, J, l+1)+λ _s π(0, J, l-1)(3)

+λ _p π(1, J-1, l-1)

When all common frequency bands in the system are used by licensed users and all reserved spectrums are used by unlicensed users, the state of the system at this time Δ ₄ ={(i,j,l)|i=0,j= J, l=L}; Can be expressed as with formula (4):

[Lμ _s +Jμ _p ]π(0,J,L)=λ _s π(0,J,L-1)+λ _p π(1,J-1,L-1)(4)

联合上述(1)、(2)、(3)和(4)可以求解稳态概率分布{π(i，j，l)|(i，j，l)∈Δ}；具体的求解方法可以参见文献《Introduction to Queueing Theory》的描述。All the steady-state probabilities in the above formulas (1), (2), (3) and (4) should satisfy the normalization constraint ∑ _{(i, j, l) ∈ Δ} π (i, j, l) = 1, in

Combining the above (1), (2), (3) and (4) can solve the steady-state probability distribution {π(i, j, l)|(i, j, l)∈Δ}; the specific solution method can be found in Description of the document "Introduction to Queueing Theory".

In the mechanism provided by the present invention, when the ordinary frequency bands are all occupied, the communication of the newly authorized users entering the network will be interrupted, and the interruption probability of the authorized users is:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}^{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; \&cup;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

When both the common frequency band and the reserved frequency band are occupied, the communication of new unauthorized users entering the network will be interrupted, and the interruption probability of unauthorized users is:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}^{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

For the unlicensed users who are communicating, when there is no idle channel, the newly authorized users entering the network will cause the interruption of the unlicensed users on the common frequency band. The calculation formula of the interruption probability is:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; Int</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\frac{\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

For the throughput of unauthorized users, the calculation formula is:

$\mathrm{<span\; class="notranslate">\; \&rho;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}\mathrm{<span\; class="notranslate">\; i\&pi;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; com</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8</span>}<span\; class="notranslate">\; )</span>$

in, $P_{\mathrm{com}}\left(L\right)=1-[P_b^{\mathrm{the\; s}}\left(L\right)+(1-P_b^{\mathrm{the\; s}}\left(L\right))\frac{{\mathrm{\&lambda;}}_p{P}_{\mathrm{Int}}\left(L\right)}{{\mathrm{\&mu;}}_{\mathrm{the\; s}}+{\mathrm{\&lambda;}}_p{P}_{\mathrm{Int}}\left(L\right)}].$

The present invention uses the Sigmoid type utility function to measure the throughput of the unauthorized user, and the specific calculation formula is as follows:

$\mathrm{<span\; class="notranslate">\; u</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&rho;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; \{</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; \&rho;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; ]</span><span\; class="notranslate">\; \}</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 9</span>}<span\; class="notranslate">\; )</span>$

Among them, g and h are constants.

In order to limit the interference to licensed users within the constraints of the outage probability and maximize the effectiveness of formula (9), it is necessary to find an optimal channel reservation number L ^* . The present invention uses P _bMAX ^p to represent the maximum interruption probability (can be set according to actual conditions) that the authorized user allows, therefore, the optimal channel reservation calculation formula is:

L ^* = arg max U

$\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; .</span><span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}^{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; bMAX</span>}}^{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10</span>}<span\; class="notranslate">\; )</span>$

Solve the formula (10) to obtain the channel number L ^* of the reserved spectrum.

When dynamically allocating the number of channels in the reserved frequency band, the channel number L ^* is obtained by solving the above method, so that the method can also guarantee the service quality of unlicensed users on the premise of ensuring the interruption probability of authorized users.

The present invention also provides a device for allocating spectrum resources in a heterogeneous wireless network. The device is shown in FIG. 2 and includes:

A judging unit 21, configured to judge whether the common frequency band is idle after receiving a request from an unlicensed user in the authorized frequency band network;

The common access unit 22 is configured to accept the request of the unlicensed user and assign the unlicensed user to a common frequency band when the judging unit judges yes;

The reserved access unit 23 is configured to receive the request of the unlicensed user and allocate the unlicensed user to the reserved frequency band when the judgment unit judges no, when the reserved frequency band is idle;

The common frequency band is: a frequency band providing services for authorized users and unlicensed users; the reserved frequency band is: a frequency band exclusively providing services for unlicensed users.

Optionally, the above-mentioned device also includes:

The switching unit 24 is configured to switch the unlicensed user to the common frequency band when it is judged that the common frequency band is free after the reserving access unit finishes allocating the unlicensed user to the reserved frequency band.

The unlicensed user in the device provided by the invention allocates the unlicensed user to the reserved frequency band when there is no idle channel in the common frequency band, thereby ensuring the Qos of the unlicensed user.

Those skilled in the art can understand that the drawing is only a schematic diagram of a preferred embodiment, and the modules or processes in the drawing are not necessarily necessary for implementing the present invention.

Those of ordinary skill in the art can understand that all or part of the steps in the methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, One or a combination of steps of the method embodiments are included.

The technical solution described in the specific embodiment of the present invention has the advantage of allocating the unlicensed users to the reserved frequency band when there is no idle channel in the common frequency band, thereby ensuring the Qos of the unlicensed users.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (5)

1. A method for allocating spectrum resources in a heterogeneous wireless network, the method comprising:

after a network of an authorized frequency band receives a request of an unauthorized user, judging whether a common frequency band is idle, if so, receiving the request of the unauthorized user, and distributing the unauthorized user to the common frequency band;

if not, receiving the request of the unauthorized user when the reserved frequency band is idle, and distributing the unauthorized user to the reserved frequency band;

the common frequency bands are: frequency bands for providing services for authorized users and unauthorized users; the reserved frequency band is as follows: a frequency band dedicated to providing service to an unauthorized user;

wherein the method further comprises:

the ordinary frequency band and the reserved frequency band are statically or dynamically configured, and when the ordinary frequency band and the reserved frequency band are dynamically configured, the method for calculating the number of the channels in the reserved frequency band comprises the following steps:

L^*＝arg max U

<math> <mrow> <mi>s</mi> <mo>.</mo> <mi>t</mi> <mo>.</mo> <mo>,</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>p</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>&lt;</mo> <msubsup> <mi>P</mi> <mi>bMAX</mi> <mi>p</mi> </msubsup> <mo>,</mo> <mi>L</mi> <mo>&le;</mo> <mi>K</mi> </mrow> </math>

wherein, s.t. is a constraint condition,

representing the maximum probability of interruption allowed by an authorized user;

solving the formula to obtain the channel number L of the reserved frequency band^*；

In the above formula:

<math> <mrow> <mi>U</mi> <mrow> <mo>(</mo> <mi>&rho;</mi> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>)</mo> </mrow> <mo>=</mo> <mfrac> <mn>1</mn> <mrow> <mn>1</mn> <mo>+</mo> <mi>exp</mi> <mo>{</mo> <mo>-</mo> <mi>g</mi> <mo>[</mo> <mi>&rho;</mi> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>h</mi> <mo>]</mo> <mo>}</mo> </mrow> </mfrac> <mo>;</mo> </mrow> </math>

<math> <mrow> <msubsup> <mi>P</mi> <mi>b</mi> <mi>p</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>3</mn> </msub> <mo>&cup;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>;</mo> </mrow> </math>

Δ₃＝{(i，j，l)|i＝0，j＝J，l＜L}；

Δ₄＝{(i，j，l)|i＝0，j＝J，l＝L}；

ρ(L)＝∑_{(i，j，l)∈Δ}iπ(i，j，l)μ_sP_com(L)；

<math> <mrow> <msub> <mi>P</mi> <mi>com</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <mn>1</mn> <mo>-</mo> <mo>[</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>+</mo> <mrow> <mo>(</mo> <mn>1</mn> <mo>-</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>)</mo> </mrow> <mfrac> <mrow> <msub> <mi>&lambda;</mi> <mi>p</mi> </msub> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> </mrow> <mrow> <msub> <mi>&mu;</mi> <mi>s</mi> </msub> <mo>+</mo> <msub> <mi>&lambda;</mi> <mi>p</mi> </msub> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> </mrow> </mfrac> <mo>]</mo> <mo>;</mo> </mrow> </math>

<math> <mrow> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>;</mo> </mrow> </math>

<math> <mrow> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mfrac> <mrow> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> </mrow> <mi>i</mi> </mfrac> <mo>;</mo> </mrow> </math>

wherein g and h are constants in the formula; l, J respectively representing the number of channels in the reserved frequency band and the number of channels in the common frequency band, K representing the total number of channels in the authorized frequency band, and pi (i, j, l) representing the steady-state probability distribution;

(i, j, l) represents the network system state of the authorized frequency band, wherein i, j and l respectively represent the number of unauthorized users occupying the ordinary frequency band, the number of authorized users occupying the ordinary frequency band and the number of unauthorized users occupying the reserved frequency band; Δ represents the state space of the system, and Δ { (i, J, L) | i + J ≦ J, L ≦ L }, where (i, J, L) is ∈ Δ; mu.s_sProbability representing service time of unauthorized user traffic; lambda [ alpha ]_pRepresenting the probability of an authorized user arriving.

2. The method of claim 1, wherein the allocating the unlicensed user to a reserved frequency band further comprises:

and when the common frequency band is idle, converting the unauthorized user into the common frequency band.

3. The method of claim 1, wherein the licensed band network comprises: 3G, WiMAX or UWB.

4. An apparatus for allocating spectrum resources in a heterogeneous wireless network, the apparatus comprising:

the judging unit is used for judging whether the common frequency band is idle or not after the network of the authorized frequency band receives the request of the unauthorized user;

a common access unit, configured to accept the request of the unauthorized user and allocate the unauthorized user to a common frequency band when the determining unit determines that the unauthorized user is authorized;

a reserved access unit, configured to receive a request of the unauthorized user when a reserved frequency band is idle and allocate the unauthorized user to the reserved frequency band when the judging unit judges that the unauthorized user is not authorized;

the common frequency bands are: frequency bands for providing services for authorized users and unauthorized users; the reserved frequency band is as follows: a frequency band dedicated to providing service to an unauthorized user;

wherein, the ordinary frequency band and the reserved frequency band in the device are obtained through static or dynamic configuration, and when the ordinary frequency band and the reserved frequency band in the device are dynamically configured, the method for calculating the number of the channels in the reserved frequency band comprises the following steps:

L^*＝arg max U

<math> <mrow> <mi>s</mi> <mo>.</mo> <mi>t</mi> <mo>.</mo> <mo>,</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>p</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>&lt;</mo> <msubsup> <mi>P</mi> <mi>bMAX</mi> <mi>p</mi> </msubsup> <mo>,</mo> <mi>L</mi> <mo>&le;</mo> <mi>K</mi> </mrow> </math>

wherein, s.t. is a constraint condition,

representing the maximum probability of interruption allowed by an authorized user;

solving the formula to obtain the channel number L of the reserved frequency band^*：

In the above formula:

<math> <mrow> <mi>U</mi> <mrow> <mo>(</mo> <mi>&rho;</mi> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>)</mo> </mrow> <mo>=</mo> <mfrac> <mn>1</mn> <mrow> <mn>1</mn> <mo>+</mo> <mi>exp</mi> <mo>{</mo> <mo>-</mo> <mi>g</mi> <mo>[</mo> <mi>&rho;</mi> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>h</mi> <mo>]</mo> <mo>}</mo> </mrow> </mfrac> <mo>;</mo> </mrow> </math>

<math> <mrow> <msubsup> <mi>P</mi> <mi>b</mi> <mi>p</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>3</mn> </msub> <mo>&cup;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>;</mo> </mrow> </math>

Δ₃＝{(i，j，l)|i＝0，j＝J，l＜L}；

Δ₄＝{(i，j，l)|i＝0，j＝J，l＝L}；

ρ(L)＝∑_{(i，j，l)∈Δ}iπ(i，j，l)μ_sP_com(L)；

<math> <mrow> <msub> <mi>P</mi> <mi>com</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <mn>1</mn> <mo>-</mo> <mo>[</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>+</mo> <mrow> <mo>(</mo> <mn>1</mn> <mo>-</mo> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>)</mo> </mrow> <mfrac> <mrow> <msub> <mi>&lambda;</mi> <mi>p</mi> </msub> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> </mrow> <mrow> <msub> <mi>&mu;</mi> <mi>s</mi> </msub> <mo>+</mo> <msub> <mi>&lambda;</mi> <mi>p</mi> </msub> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> </mrow> </mfrac> <mo>]</mo> <mo>;</mo> </mrow> </math>

<math> <mrow> <msubsup> <mi>P</mi> <mi>b</mi> <mi>s</mi> </msubsup> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>;</mo> </mrow> </math>

<math> <mrow> <msub> <mi>P</mi> <mi>Int</mi> </msub> <mrow> <mo>(</mo> <mi>L</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&Sigma;</mi> <mrow> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> <mo>&Element;</mo> <msub> <mi>&Delta;</mi> <mn>4</mn> </msub> </mrow> </msub> <mfrac> <mrow> <mi>&pi;</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>,</mo> <mi>j</mi> <mo>,</mo> <mi>l</mi> <mo>)</mo> </mrow> </mrow> <mi>i</mi> </mfrac> <mo>;</mo> </mrow> </math>

wherein g and h are constants in the formula; l, J respectively representing the number of channels in the reserved frequency band and the number of channels in the common frequency band, K representing the total number of channels in the authorized frequency band, and pi (i, j, l) representing the steady-state probability distribution;

(i, J, L) represents a network system state of an authorized frequency band, wherein i, J and L respectively represent the number of unauthorized users occupying a common frequency band, the number of authorized users occupying the common frequency band and the number of unauthorized users occupying a reserved frequency band, Δ represents a state space of the system, and Δ { (i, J, L) | i + J ≦ J, L ≦ L }, wherein (i, J, L) belongs to Δ; mu.s_sProbability representing service time of unauthorized user traffic; lambda [ alpha ]_pRepresenting the probability of an authorized user arriving.

5. The apparatus of claim 4, further comprising:

and the conversion unit is used for converting the unauthorized user into the common frequency band when the common frequency band is judged to be idle after the reserved access unit finishes distributing the unauthorized user to the reserved frequency band.

Images