WO2018040358A1

WO2018040358A1 - Frequency spectrum access method and apparatus

Info

Publication number: WO2018040358A1
Application number: PCT/CN2016/109475
Authority: WO
Inventors: 李佳悦; 倪明选
Original assignee: 广州市香港科大霍英东研究院
Priority date: 2016-08-31
Filing date: 2016-12-12
Publication date: 2018-03-08
Also published as: CN106304103A; CN106304103B

Abstract

Respecting the condition of a multi-channel wireless network using a time domain separation method to achieve basic communication coexistence, the present invention discloses a frequency spectrum access method, comprising: selecting from amongst all the LTE-U users in the multi-channel wireless network an LTE-U user Cell_i to co-work with 802.11 users; when (m-1) groups of 802.11 users on a different channel to the LTE-U user Cell_i respectively access an ith wireless channel, calculating the throughput respectively acquired by the (m-1) groups of 802.11 users and the throughput attenuation caused to the LTE-U user Cell_i; and selecting a group of 802.11 users therefrom to access the ith wireless channel in an LTE-U time period. Also disclosed in the present invention is a frequency spectrum access apparatus. The present invention achieves the objective of improving the throughput of 802.11 users and the global network when 802.11 users and LTE-U users coexist.

Description

Spectrum access method and device

Technical field

The present invention relates to the field of communications, and in particular, to a spectrum access method and apparatus.

Background technique

LTE (Long Term Evolution) is a long-term evolution of the UMTS (Universal Mobile Telecommunications System) technology standard developed by the 3GPP (The 3rd Generation Partnership Project). Worldwide, due to the dramatic increase in demand for existing LTE services and the shortage of available spectrum resources, many ICT companies and operators have begun to explore and evaluate the feasibility of using unlicensed bands. Three of them are located in the U-NII band near 5GHz: U-NII-1 (5150-5250MHz), U-NII-2 (5250-5725MHz) and U-NII-3 (5725-5850MHz) are considered to be very suitable for the future. Spectrum resources provided to new LTE services. For the LTE service proposed to operate in this band, we call it LTE-U or LTE service (LAA) in the unlicensed band. Some ICT companies and operators have also evaluated the use of this band and believe that this LTE service extended to the unlicensed band will largely alleviate the excessive demand in the licensed band. The resulting user experience issues, as well as the efficiency of spectrum usage. For example, in the Release 13 standard in 3GPP, a downlink LTE signal transmission service that is extended to the 5 GHz band using carrier aggregation technology is proposed.

However, compared to the LTE services currently used in licensed bands, LTE-U will work on the same channel as many of today's unlicensed bands, resulting in mutual signal interference and collision problems. Of the wireless LAN services currently operating on unlicensed bands, the most common and widely used is the 802.11 family, which is the router or Wi-Fi service we usually refer to. Since the base station of the LTE-U in the future is likely to be placed in the home or indoor public environment, the possibility that the Wi-Fi transmitting end and the LTE-U downlink transmission transmitting end coexist in the same local area network is increased. Therefore, the reasonable coexistence between LTE-U and 802.11 family devices will be a focus of today and the future.

LTE-U is the future licensed spectrum service, while 802.11 devices are mostly unlicensed spectrum services working on the ISM band. Therefore, the most essential difference between the two is that the LTE-U series of user services will be protected first. The 802.11 service can only be carried out without guaranteeing serious impact on the licensed spectrum users. Another significant difference between the two is the control and protection plane that they use to maintain and improve the quality of service. LTE-U will inherit most of the control planes of LTE services in the original 3GPP, and manage each spectrum access or data transmission of its user data streams very efficiently and orderly. The characteristics of 802.11 low-cost services also affect its control plane, which is mainly based on CSMA/CA mechanism or energy detection method. To control access and idleness of the spectrum. Therefore, when LTE-U and 802.11 devices coexist in a limited local area network, the 802.11 device will actively evade the LTE-U service that is using the spectrum due to its characteristics as an unlicensed spectrum user. At the same time, because of the simple spectrum access protocol of 802.11 devices, when multiple LTE-U users compete for the same channel at the same time, 802.11 services will even tend to terminate. In this case, the user experience of 802.11 users will be experienced. It has a very serious negative impact. Although LTE-U services need to be authorized to protect, 802.11 technology is very mature and widely distributed in our lives, and has become a very efficient and convenient way to access the Internet. Therefore, how to maximize the transmission throughput of 802.11 under the LTE-U user experience will become a crucial research topic in the coexistence of the two.

In the existing solutions, CSAT (Carrier Sensing Adaptive Transmission) and LBT (Listen-before-Talk) are used to regulate LTE-U and 802.11. Transmission between devices and spectrum access. The basic idea of CSAT is to achieve coexistence between LTE-U and 802.11 by setting a loop interval and occupancy time ratio of a certain length. Essentially a method of time domain management. This method can directly avoid the signal interference problem between LTE-U and 802.11 devices due to the shared spectrum. Although CSAT isolates the two signals in the most direct way, thus avoiding the conflict between the two, it is both the advantage of this method and its shortcomings. The disadvantage is that when we set the length of a specific loop interval and the time ratio of the two signals, the LTE-U interval will completely isolate any service of 802.11, which greatly reduces the throughput of 802.11 from the time domain. . Another evaluation result shows that when LTE-U accesses its cyclic working cycle, it does not perform channel detection like 802.11 devices, but directly accesses the channel, which will interfere with the still working 802.11 service. , causing a drop in throughput. Moreover, in the case of a fixed loop interval length, as the LTE-U occupied loop interval time ratio increases, the throughput of 802.11 users will also drop significantly.

The LBT mechanism refers to detecting the spectrum and determining whether the channel is idle before the LTE-U and 802.11 transmit in the occupied spectrum. If the channel is idle, one of the two can declare that the channel will be used, thereby avoiding the interference problem caused by the simultaneous transmission of both.

Compared with CSAT, the mechanism of LBT is more "civilized", because LTE-U and 802.11 will detect and declare the spectrum to be used before accessing the spectrum. However, the LBT mechanism of 802.11 also includes Random Backoff and Exponential Backoff. The basic idea of the two avoidance methods is to add a period of time before accessing the spectrum to detect whether or not other users use the spectrum during this time. This kind of waiting will greatly increase the access possibility of LTE-U, which causes the transmission of 802.11 to wait for a long time, and the final throughput is greatly reduced.

In the prior art, the solution of coexistence of LTE-U and 802.11, the throughput of 802.11 users is greatly affected, and the throughput of 802.11 users cannot be improved.

Summary of the invention

The object of the present invention is to provide a spectrum access method, which solves the problem of how to improve the throughput of 802.11 users and the global network as much as possible when multiple LTE-U users and multiple 802.11 users coexist in multiple channels respectively. .

To achieve the above objective, the present invention provides a spectrum access method, including:

Setting a cyclic time interval for each wireless channel in the multi-channel wireless network according to a carrier sense adaptive transmission protocol; wherein the multi-channel wireless network includes m wireless channels, each of which is a group of LTE -U user and a group of 802.11 users occupied;

Allocating an LTE-U time period and an 802.11 time period in each of the wireless channels; wherein the LTE-U time period is a time zone occupied by an LTE-U user of the wireless channel in the cycle time interval, The 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

Selecting a group of LTE-U users from all the LTE-U users in the multi-channel wireless network as the LTE-U user Cell _i to be cooperating with the 802.11 user;

Calculating ( _i -1) group 802.11 users that are in different channels with the LTE-U user Cell _i when accessing the ith radio channel where the LTE-U user Cell _i is located in the LTE-U time period The throughput obtained by the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell _i ;

According to the throughput obtained by the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell _i , one set of 802.11 is selected. The user accesses the ith radio channel in the LTE-U time period.

The implementation of the present invention has the following beneficial effects:

The spectrum access method provided by the present invention, on the basis of the existing time domain management mode CSAT, encourages 802.11 users to selectively access the time period of the adjacent non-local LTE-U when the local channel LTE-U user occupies the spectrum. By calculating the throughput obtained when the 802.11 user accesses the channel where the LTE-U user is located, and the throughput attenuation caused by the LTE-U user Cell _i respectively, selecting an appropriate 802.11 user to access the non-local channel to ensure the 802.11 user. The access will not cause unacceptable interference to the LTE-U users in use, that is, balance the throughput that 802.11 users can increase and their impact on LTE-U user throughput, so that 802.11 users and LTE-U users coexist. To improve the throughput of 802.11 users and the global network.

Further, the LTE-U user is selected from all the LTE-U users in the multi-channel wireless network as the LTE-U user Cell _i to be worked with the 802.11 user, and specifically includes:

Comparing bandwidths of each group of the LTE-U users in the multi-channel wireless network;

The LTE-U user with the smallest bandwidth is selected as the LTE-U user Cell _{i to} work with the 802.11 user.

In a further solution, the process of selecting the LTE-U user Cell _{i to} work with the 802.11 user is selected according to the bandwidth of the LTE-U user, and the spectrum gap generated after the channel superposition can be utilized to obtain the 802.11 user for a greater degree. The most throughput.

Further, the calculating (m-1) group 802.11 users that are in different channels with the LTE-U user Cell _i access the LTE-U user Cell _i in the LTE-U time period respectively. The throughput obtained by the (m-1) group 802.11 users and the throughput attenuation caused by the (m-1) group 802.11 users to the LTE-U user Cell _i , respectively, when i are wireless channels, Specifically include:

Extracting (m-1) groups of 802.11 users WLAN ₁ to WLAN _{m-1 that} are in different channels from the LTE-U user Cell _i ;

Selecting, from the (m-1) group 802.11 user WLAN ₁ to WLAN _m-1 , a group of 802.11 users accessing the ith wireless device where the LTE-U user Cell _i is located in the LTE-U time period. Channel, calculated throughput T _ij , and throughput attenuation D _ij ;

Wherein, the throughput T _ij is obtained when the jth group 802.11 user WLAN _j accesses the ith radio channel where the LTE-U user Cell _i is located in the LTE-U time period, and the 802.11 user WLAN _j obtains The throughput attenuation D _ij is the 802.11 when the _ith 802.11 user WLAN _j accesses the ith radio channel where the LTE-U user Cell _i is located in the LTE-U time period. The throughput attenuation caused by the user WLAN _j to the LTE-U user Cell _i ; 1 ≤ _j ≤ m-1.

In one embodiment, the throughput obtained according to the (m-1) group 802.11 user respectively, and the throughput of the (m-1) group 802.11 user respectively to the LTE-U user Cell _i The amount of the amount of attenuation is selected, and one of the 802.11 users is selected to access the ith radio channel in the LTE-U time period, which specifically includes:

Calculating (m-1) balance variable values K ₁ to K _m-1 corresponding to the (m-1) group 802.11 users one by _one ; wherein K _j =T _ij /D _ij ;

Comparing the (m-1) balance variable values K ₁ to K _m-1 , and setting a group of 802.11 users with the largest balance variable value as the 802.11 user WLAN _{x that} can access the ith wireless channel;

And setting the 802.11 user WLAN _x to access the ith radio channel in the LTE-U time period.

In one of the embodiments, the balance variable value is set. The significance of the balance variable value setting is to find the balance between the throughput that is improved for 802.11ac and the throughput that is reduced when LTE-U is interfered. When the balance variable value is 1, the throughput of 802.11 is improved with LTE-U. The reduced throughput at the time of interference reaches equilibrium. The larger the value of the balance variable, the more the global network throughput is increased, which directly and effectively improves the throughput of the global network.

In another embodiment, the throughput obtained according to the (m-1) group 802.11 user respectively, and the throughput of the (m-1) group 802.11 user respectively to the LTE-U user Cell _i The amount of the amount of attenuation is selected, and one of the 802.11 users is selected to access the ith radio channel in the LTE-U time period, which specifically includes:

Select n groups of 802.11 users whose throughput attenuation is less than 13%;

Comparing the n balance variable values corresponding to the n groups of 802.11 users, and setting a group of 802.11 users with the largest balance variable value as the 802.11 user WLAN _x capable of accessing the ith wireless channel;

In another embodiment, 802.11 users with less than 13% throughput degradation for LTE-U users can be accessed to the ith radio channel. According to the experimental results of the inventors, on the basis of sacrificing the throughput of 9% of LTE-U, the throughput of 802.11 is balanced with the throughput reduced when LTE-U is interfered, and 13% is set as the throughput attenuation. The threshold value can ensure that the BER of the LTE-U channel quality is not lower than the level of 1.0e-2. LTE-U is a future licensed spectrum service, and guaranteeing its channel quality is beneficial to improve the practicability of the present invention.

Correspondingly, the present invention also provides a spectrum access apparatus, including:

a time domain setting module, configured to set a cycle time interval for each wireless channel in the multi-channel wireless network according to the carrier sense adaptive transmission protocol; wherein the multi-channel wireless network includes m wireless channels, each of the The wireless channel is occupied by a group of LTE-U users and a group of 802.11 users;

a parameter setting module, configured to allocate an LTE-U time period and an 802.11 time period in each of the wireless channels; wherein the LTE-U time period is an LTE-U user of the wireless channel in the cycle time interval a time zone occupied internally, wherein the 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

An LTE-U user selection module, configured to select a group of LTE-U users from all the LTE-U users in the multi-channel wireless network, as an LTE-U user Cell _i to be cooperating with an 802.11 user;

a variable calculation module, configured to calculate (m-1) group 802.11 users that are in different channels from the LTE-U user Cell _i , accessing the LTE-U user Cell _i in the LTE-U time period respectively The throughput of the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users to the LTE-U user Cell _i respectively. ;

a spectrum assembling module, configured to obtain a throughput attenuation according to the (m-1) group 802.11 user respectively, and a throughput attenuation caused by the (m-1) group 802.11 user to the LTE-U user Cell _i And selecting one of the 802.11 users to access the ith radio channel during the LTE-U time period.

The spectrum access device provided by the present invention, based on the existing time domain management mode CSAT, encourages 802.11 users to selectively access the time period of the adjacent non-local LTE-U when the local channel LTE-U user occupies the spectrum. By calculating the throughput obtained when the 802.11 user accesses the channel where the LTE-U user is located, and the throughput attenuation caused by the LTE-U user Cell _i respectively, selecting an appropriate 802.11 user to access the non-local channel to ensure the 802.11 user. The access will not cause unacceptable interference to the LTE-U users in use, that is, balance the throughput that 802.11 users can increase and their impact on LTE-U user throughput, so that 802.11 users and LTE-U users coexist. To improve the throughput of 802.11 users and the global network.

Further, the LTE-U user selection module includes:

a bandwidth comparison unit, configured to compare bandwidths of each group of the LTE-U users in the multi-channel wireless network;

The selecting unit is configured to select an LTE-U user with the smallest bandwidth as the LTE-U user Cell _i to be cooperating with the 802.11 user.

Further, the variable calculation module includes:

An extracting unit, configured to extract (m-1) group 802.11 users WLAN ₁ to WLAN _{m-1 that} are in different channels from the LTE-U user Cell _i ;

a throughput calculation unit, configured to sequentially select a group of 802.11 users from the (m-1) group 802.11 users WLAN ₁ to WLAN _m-1 to access the LTE-U user cell in the LTE-U time period _{The i-} th wireless channel where _i is located, the throughput T _ij , and the throughput attenuation amount D _ij ;

In one embodiment, the spectrum mosaic module includes:

a balance variable calculation unit for calculating (m-1) balance variable values K ₁ to K _m-1 corresponding to the (m-1) group 802.11 users; wherein K _j =T _ij /D _ij ;

The 802.11 user selection unit is configured to compare the (m-1) balance variable values K ₁ to K _m-1 , and set a group of 802.11 users with the largest balance variable value as the 802.11 user who can access the i th wireless channel. WLAN _x ;

And a setting unit, configured to set the 802.11 user WLAN _x to access the ith radio channel in the LTE-U time period.

In another embodiment, the spectrum access module includes:

The attenuation amount screening unit is configured to select n groups of 802.11 users whose throughput attenuation is less than 13%;

An 802.11 user selection unit is configured to compare n balance variable values corresponding to the n groups of 802.11 users, and set a group of 802.11 users with the largest balance variable value as an 802.11 user WLAN _{x that} can access the ith wireless channel;

DRAWINGS

FIG. 1 is a flowchart of Embodiment 1 of a spectrum access method provided by the present invention:

2 is a flowchart of Embodiment 2 of a spectrum access method provided by the present invention;

3 is a schematic diagram of spectrum access according to Embodiment 2 of a spectrum access method provided by the present invention;

4 is a structural block diagram of a spectrum access apparatus provided by the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

FIG. 1 is a flowchart of Embodiment 1 of a spectrum access method provided by the present invention. In this embodiment, a spectrum access method includes:

S11. Set a cycle time interval for each wireless channel in the multi-channel wireless network according to the carrier sense adaptive transmission protocol, where the multi-channel wireless network includes m wireless channels, and each of the wireless channels is Group LTE-U users and a group of 802.11 users occupy;

S12. Allocating an LTE-U time period and an 802.11 time period in each of the wireless channels, where the LTE-U time period is a time occupied by an LTE-U user of the wireless channel in the cycle time interval a region, where the 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

S13, selecting a group of LTE-U users from all the LTE-U users in the multi-channel wireless network, as an LTE-U user Cell _i to be cooperating with an 802.11 user;

S14. The (m-1) group 802.11 user that is in a different channel from the LTE-U user Cell _i accesses the ith wireless device where the LTE-U user Cell _i is located in the LTE-U time period. The throughput obtained by the (m-1) group 802.11 users and the throughput attenuation caused by the (m-1) group 802.11 users to the LTE-U user Cell _i respectively;

S15. Select, according to the throughput obtained by the (m-1) group 802.11 user, and the throughput attenuation caused by the (m-1) group 802.11 user respectively to the LTE-U user Cell _i . A group 802.11 user accesses the ith radio channel during the LTE-U time period.

The first embodiment of the spectrum access method provided by the present invention, based on the existing time domain management mode CSAT, encourages 802.11 users to selectively access the time period of the adjacent non-local LTE-U when the local channel LTE-U user occupies the spectrum. That is, the LTE-U user selects a suitable 802.11 user to access the wireless channel where the LTE-U user is located, so that the 802.11 user accesses the channel where the LTE-U user is located when the local 802.11 time period cannot work. To improve the throughput of 802.11 users; to select the appropriate 802.11 users by calculating the throughput obtained when the 802.11 user accesses the channel where the LTE-U user is located, and the throughput attenuation caused by the LTE-U user Cell _i respectively. Accessing non-local channels ensures that 802.11 user access does not cause unacceptable interference to LTE-U users in use, ie balancing the increased throughput of 802.11 users and their impact on LTE-U user throughput, Colleagues whose 802.11 users have improved throughput, the throughput of LTE-U users has not dropped too much; when 802.11 users coexist with LTE-U users, the throughput of 802.11 users and the global network is improved.

In this embodiment, in the specific implementation, the set W and the set L are first established, and the set W and L respectively include all 802.11 users and LTE-U users, that is, W={WLAN ₁ , WLAN ₂ , WLAN ₃ , . . . , WLAN _m } , L = {Cell ₁ , Cell ₂ , Cell ₃ , ..., Cell _m }. First, the first group of LTE-U user Cell ₁ is extracted from the set L, and the 802.11 users on the non-first channel, that is, the 802.11 users on the second channel to the mth channel, respectively, are obtained in the set W. The throughput and the amount of throughput attenuation caused by it, so as to select the 802.11 user WLAN _j that is most suitable for accessing the wireless channel where the LTE-U user Cell ₁ is located, and access the wireless channel where the LTE-U user Cell ₁ is located. ;

Then, WLAN _j is removed from the set W, the set W is updated; the second group of LTE-U users Cell ₂ is extracted from the set L, and the non-second channel is selected from the set W, which is most suitable for accessing the second group of LTE. Cell ₂ -U user where the user radio channel 802.11 WLAN _k, user access to the radio channel LTE-U Cell ₂ is located;

And so on, calculating the throughput obtained by the 802.11 user when the 802.11 user accesses the i th wireless channel in the LTE-U time period, and the 802.11 user to the LTE-U, for the i-th group user Cell _i in the set L The throughput attenuation caused by the user Cell _i ; according to the throughput and the throughput attenuation amount, one of the 802.11 users is selected to access the ith radio channel in the LTE-U time period.

FIG. 2 is a schematic diagram of spectrum access according to Embodiment 2 of the spectrum access method provided by the present invention; in this embodiment, Spectrum access methods include:

S21. Set a cycle time interval for each wireless channel in the multi-channel wireless network according to the carrier sense adaptive transmission protocol, where the multi-channel wireless network includes m wireless channels, and each of the wireless channels is Group LTE-U users and a group of 802.11 users occupy;

S22. Allocating an LTE-U time period and an 802.11 time period in each of the wireless channels, where the LTE-U time period is a time occupied by an LTE-U user of the wireless channel in the cycle time interval. a region, where the 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

S23. Select a group of LTE-U users from all the LTE-U users in the multi-channel wireless network, as the LTE-U user Cell _i to be cooperating with the 802.11 user, specifically: comparing the multiple channels. The bandwidth of each group of the LTE-U users in the wireless network; the LTE-U user with the smallest bandwidth is selected as the LTE-U user Cell _i to be cooperating with the 802.11 user;

S24. The (m-1) group 802.11 user that is in a different channel from the LTE-U user Cell _i accesses the ith wireless device where the LTE-U user Cell _i is located in the LTE-U time period. The throughput obtained by the (m-1) group 802.11 users and the throughput attenuation caused by the (m-1) group 802.11 users to the LTE-U user Cell _i respectively;

S25. Select, according to the throughput obtained by the (m-1) group 802.11 user, and the throughput attenuation caused by the (m-1) group 802.11 user to the LTE-U user Cell _i , respectively. A group 802.11 user accesses the ith radio channel during the LTE-U time period.

In this embodiment, step S24 "calculates that (m-1) group 802.11 users who are in different channels with the LTE-U user Cell _i access the LTE-U user Cell _i in the LTE-U time period respectively. The throughput of the (m-1) group of 802.11 users and the throughput of the (m-1) group of 802.11 users respectively to the LTE-U user Cell _i when the i-th wireless channel is located The amount of attenuation, including:

Step S25: "According to the throughput obtained by the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell _i , A group of 802.11 users accessing the ith radio channel during the LTE-U time period, which specifically includes:

Select n groups of 802.11 users whose throughput attenuation is less than 13%;

This embodiment has made several improvements on the basis of the first embodiment. In the process of selecting the LTE-U user Cell _{i to} work with the 802.11 user, this embodiment compares the bandwidth of all LTE-U users, and preferentially selects 802.11 users to access their channels for the LTE-U users with small bandwidth.

According to the types of bandwidth used by 3GPP LTE technology, mainly based on 20MHz, 15MHz, 10MHz, 5MHz, 3MHz, and 1.4MHz, providing better user experience and data transmission through carrier aggregation technology; and 802.11 working in the 5GHz band. The bandwidth of the device is doubled to 40MHz, 80MHz or even 160MHz based on 20MHz. Therefore, when LTE-U and 20MHz 802.11 devices work in the 5GHz band, LTE-U signals aggregated at 15MHz, 10MHz, 5MHz, 3MHz, and 1.4MHz bandwidth may generate spectrum gaps of different sizes. Therefore, in the process of selecting the LTE-U user Cell _{i to} work with the 802.11 user, according to the bandwidth of the LTE-U user, the spectrum gap generated after the channel superposition can be utilized to obtain the most 802.11 users. Throughput.

In addition, the embodiment sets the balance variable value, and the balance variable value setting means finding the balance point between the throughput improved by 802.11ac and the throughput reduced when LTE-U is interfered, when the balance variable value is 1. The throughput that is increased for 802.11 is balanced with the reduced throughput when LTE-U is interfered. The larger the value of the balance variable, the more the global network throughput is increased, which directly and effectively improves the throughput of the global network. In this embodiment, the threshold filtering is performed on the throughput attenuation amount, and then the 802.11 user with the large balance variable value is selected to access the non-local channel.

3 is a schematic diagram of spectrum access according to Embodiment 2 of the spectrum access method provided by the present invention; as shown in FIG. 3, initially there are three LTE-U users and three 802.11 users, and a set L={Cell _{1 is established.} , Cell ₂ , Cell ₃ }, set W = {WLAN ₁ , WLAN ₂ , WLAN ₃ }. In the case of three LTE-U users, Cell ₁ and 20MHz 802.11 signals are superimposed to provide the most white space spectrum, reaching 15MHz. Therefore, we first select the appropriate 802.11 user for Cell ₁ to access its channel. According to the screening of the throughput attenuation, more than 13% will be abandoned, and no more than 13% will be selected according to the value of the balance variable. The larger the value of the balance variable will be preferentially accessed. As shown in Figure 3, the access of WLAN ₁ exceeds the threshold of throughput attenuation, so it is abandoned, and the access of WLAN ₂ and WLAN ₃ does not exceed the attenuation threshold, but the access of WLAN ₃ Let the balance variable value be larger, so in the end we return the combination of {Cell ₁ , WLAN ₃ } as a working LTE-U user and 802.11 user.

It should be noted that, in the embodiment, the same as the first embodiment, after selecting an LTE-U user and selecting a suitable 802.11 user access, the 802.11 user set is updated, and the second group of LTE-U is selected. The user, the largest group of LTE-U users among the remaining LTE-U users, selects the appropriate 802.11 user access for it. By analogy, try to select the appropriate 802.11 user access for each group of LTE-U users to maximize the throughput of the global network.

In this embodiment, the 802.11 user that sets the throughput attenuation caused by the LTE-U user to be less than 13% can be accessed by the ith radio channel to ensure the quality of the LTE-U channel and avoid the 802.11 user access. The impact on LTE-U users is too large.

Since the LTE-U service has not yet been put into practical use, the inventors used a vector signal generator as a signal source, and additionally used a signal analyzer to analyze the effects of the LTE-U and 802.11ac partial bandwidth superposition. In order to construct the real interference between LTE-U and 802.11ac signals according to the real scene, the influence of LTE-U on the signal strength of 802.11 is fixed, and the influence of the LTE-U transmitter on the signal strength of the 802.11ac receiver and LTE- The base station of U affects the signal strength of the LTE-U receiver. In the experiment, the SystemVue software platform was also used to simulate the LTE-U signal throughput when LTE-U and 802.11ac signal interference. By adjusting the signal strength of the 802.11ac signal, adjusting the access threshold of the throughput D _ij and the throughput attenuation D _ij , it is finally confirmed that the 802.11 user can improve the throughput by sacrificing the throughput of 9% of the LTE-U. The amount and its impact on the LTE-U user throughput are balanced, and finally 13% is set as a threshold for the LTE-U attenuation value, ensuring that the channel quality BER of the LTE-U is not lower than the 1.0e-2 level. LTE-U is a future licensed spectrum service, and guaranteeing its channel quality is beneficial to improve the practicability of the present invention.

Using the above experimental results, the inventor constructed a five-channel wireless network using a CSAT protocol with a LTE-U time period and an 802.11 time period ratio of 1:1, each cycle period being 50 ms, and the total transmission time being 500 ms, according to this implementation. The spectrum access algorithm provided by the example simulates the spectrum access process, and finally increases the throughput of 802.11 users by about 40% on five channels and 28% of the throughput for the global network. Therefore, the spectrum access method provided by the present invention can effectively achieve the purpose of improving the throughput of 802.11 users and the global network.

It should be noted that the spectrum access method provided by the present invention may aggregate multiple channels of different or the same bandwidth based on a carrier aggregation technology, that is, each wireless channel in the present invention may include multiple different or the same bandwidth. Aggregate, each A group of LTE-U users on a wireless channel may include more than one LTE-U user.

In this embodiment, the threshold filtering is performed on the throughput attenuation amount, and then the 802.11 user with the large balance variable value is selected to access the non-local channel, wherein the throughput attenuation threshold is set to 13%, which is only one preferred embodiment. In other embodiments, the 802.11 user may be selected by directly comparing the balance variable values without threshold filtering; or other thresholds may be set, and the present invention is not limited thereto. That is, in step S25, "the throughput obtained according to the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell _i , A group of 802.11 users accessing the ith radio channel during the LTE-U time period may also be implemented by the following steps:

Correspondingly, the present invention further provides a spectrum access device. Referring to FIG. 4, it is a structural block diagram of a spectrum access device provided by the present invention, including:

The time domain setting module 31 is configured to set a cycle time interval for each wireless channel in the multi-channel wireless network according to the carrier sense adaptive transmission protocol; wherein the multi-channel wireless network includes m wireless channels, each of which The wireless channels are occupied by a group of LTE-U users and a group of 802.11 users;

a parameter setting module 32, configured to allocate an LTE-U time period and an 802.11 time period in each of the wireless channels; wherein the LTE-U time period is an LTE-U user of the wireless channel at the cycle time a time zone occupied by the interval, wherein the 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

The LTE-U user selection module 33 is configured to select a group of LTE-U users from all the LTE-U users in the multi-channel wireless network, as the LTE-U user Cell _i to be cooperating with the 802.11 user;

The variable calculation module 34 is configured to calculate (m-1) group 802.11 users that are in different channels from the LTE-U user Cell _i to access the LTE-U user Cell _i in the LTE-U time period respectively. The throughput of the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell _i the amount;

a spectrum assembling module 35, configured to perform throughput according to the (m-1) group 802.11 user respectively, and the throughput of the (m-1) group 802.11 user respectively to the LTE-U user Cell _i The amount of attenuation is selected by one of the 802.11 users to access the ith radio channel during the LTE-U time period.

Further, the LTE-U user selection module includes:

Further, the variable calculation module includes:

In one embodiment, the spectrum mosaic module includes:

In another embodiment, the spectrum access module includes:

a balance variable calculation unit for calculating (m-1) balance variables K ₁ to K _m-1 corresponding to the (m-1) group 802.11 users; wherein K _j =T _ij /D _ij ;

And a setting unit, configured to set the 802.11 user WLAN _x to access the ith wireless channel during the LTE-U time period.

The spectrum access method and device provided by the present invention, based on the existing time domain management mode CSAT, encourages 802.11 users to selectively access the time period of the adjacent non-local LTE-U when the local channel LTE-U user occupies the spectrum. By calculating the throughput obtained when the 802.11 user accesses the channel where the LTE-U user is located, and the throughput attenuation caused by the LTE-U user Cell _i respectively, selecting an appropriate 802.11 user to access the non-local channel to ensure the 802.11 user. The access will not cause unacceptable interference to the LTE-U users in use, that is, balance the throughput that 802.11 users can increase and their impact on LTE-U user throughput, so that 802.11 users and LTE-U users coexist. To improve the throughput of 802.11 users and the global network.

The above is a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and modifications without departing from the principles of the present invention. The scope of protection of the invention.

Claims

A spectrum access method, comprising:

Setting a cyclic time interval for each wireless channel in the multi-channel wireless network according to a carrier sense adaptive transmission protocol; wherein the multi-channel wireless network includes m wireless channels, each of which is a group of LTE -U user and a group of 802.11 users occupied;

Allocating an LTE-U time period and an 802.11 time period in each of the wireless channels; wherein the LTE-U time period is a time zone occupied by an LTE-U user of the wireless channel in the cycle time interval, The 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

Selecting a group of LTE-U users from all the LTE-U users in the multi-channel wireless network as the LTE-U user Cell i to be cooperating with the 802.11 user;

Calculating ( i -1) group 802.11 users that are in different channels with the LTE-U user Cell i when accessing the ith radio channel where the LTE-U user Cell i is located in the LTE-U time period The throughput obtained by the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell i ;

According to the throughput obtained by the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users respectively to the LTE-U user Cell i , one set of 802.11 is selected. The user accesses the ith radio channel in the LTE-U time period.
The spectrum access method according to claim 1, wherein said selecting a group of LTE-U users from all of said LTE-U users in said multi-channel wireless network as working together with 802.11 users The LTE-U user Cell i specifically includes:

Comparing bandwidths of each group of the LTE-U users in the multi-channel wireless network;

The LTE-U user with the smallest bandwidth is selected as the LTE-U user Cell i to work with the 802.11 user.
The spectrum access method according to claim 1 or 2, wherein the (m-1) group 802.11 users that are in different channels from the LTE-U user Cell i are respectively in the LTE-U time. The throughput obtained by the (m-1) group 802.11 users and the (m-1) group 802.11 users respectively when accessing the ith radio channel where the LTE-U user Cell i is located in the period The throughput attenuation caused by the LTE-U user Cell i specifically includes:

Extracting (m-1) groups of 802.11 users WLAN 1 to WLAN m-1 that are in different channels from the LTE-U user Cell i ;

Selecting, from the (m-1) group 802.11 user WLAN 1 to WLAN m-1 , a group of 802.11 users accessing the ith wireless device where the LTE-U user Cell i is located in the LTE-U time period. Channel, calculated throughput T ij , and throughput attenuation D ij ;

Wherein, the throughput T ij is obtained when the jth group 802.11 user WLAN j accesses the ith radio channel where the LTE-U user Cell i is located in the LTE-U time period, and the 802.11 user WLAN j obtains The throughput attenuation D ij is the 802.11 when the ith 802.11 user WLAN j accesses the ith radio channel where the LTE-U user Cell i is located in the LTE-U time period. The throughput attenuation caused by the user WLAN j to the LTE-U user Cell i ; 1 ≤ j ≤ m-1.
The spectrum access method according to claim 3, wherein said throughput is respectively obtained according to said (m-1) group 802.11 users, and said (m-1) group 802.11 users respectively The amount of throughput attenuation caused by the LTE-U user Cell i , selecting one of the 802.11 users, and accessing the ith radio channel in the LTE-U time period, specifically includes:

Calculating (m-1) balance variable values K 1 to K m-1 corresponding to the (m-1) group 802.11 users one by one ; wherein K j =T ij /D ij ;

Comparing the (m-1) balance variable values K 1 to K m-1 , and setting a group of 802.11 users with the largest balance variable value as the 802.11 user WLAN x that can access the ith wireless channel;

And setting the 802.11 user WLAN x to access the ith radio channel in the LTE-U time period.
The spectrum access method according to claim 3, wherein said throughput is respectively obtained according to said (m-1) group 802.11 users, and said (m-1) group 802.11 users respectively The amount of throughput attenuation caused by the LTE-U user Cell i , selecting one of the 802.11 users, and accessing the ith radio channel in the LTE-U time period, specifically includes:

Calculating (m-1) balance variable values K 1 to K m-1 corresponding to the (m-1) group 802.11 users one by one ; wherein K j =T ij /D ij ;

Selecting n groups of 802.11 users whose throughput attenuation is less than 13%;

Comparing the n balance variable values corresponding to the n groups of 802.11 users, and setting a group of 802.11 users with the largest balance variable value as the 802.11 user WLAN x capable of accessing the ith wireless channel;

And setting the 802.11 user WLAN x to access the ith radio channel in the LTE-U time period.
A spectrum access device, comprising:

a time domain setting module, configured to set a cycle time interval for each wireless channel in the multi-channel wireless network according to the carrier sense adaptive transmission protocol; wherein the multi-channel wireless network includes m wireless channels, each of the The wireless channel is occupied by a group of LTE-U users and a group of 802.11 users;

a parameter setting module, configured to allocate an LTE-U time period and an 802.11 time period in each of the wireless channels; wherein the LTE-U time period is an LTE-U user of the wireless channel in the cycle time interval a time zone occupied internally, wherein the 802.11 time period is a time zone occupied by an 802.11 user of the wireless channel in the cycle time interval;

An LTE-U user selection module, configured to select a group of LTE-U users from all the LTE-U users in the multi-channel wireless network, as an LTE-U user Cell i to be cooperating with an 802.11 user;

a variable calculation module, configured to calculate (m-1) group 802.11 users that are in different channels from the LTE-U user Cell i , accessing the LTE-U user Cell i in the LTE-U time period respectively The throughput of the (m-1) group 802.11 users respectively, and the throughput attenuation caused by the (m-1) group 802.11 users to the LTE-U user Cell i respectively. ;

a spectrum assembling module, configured to obtain a throughput attenuation according to the (m-1) group 802.11 user respectively, and a throughput attenuation caused by the (m-1) group 802.11 user to the LTE-U user Cell i And selecting one of the 802.11 users to access the ith radio channel during the LTE-U time period.
The spectrum access device of claim 6, wherein the LTE-U user selection module comprises:

a bandwidth comparison unit, configured to compare bandwidths of each group of the LTE-U users in the multi-channel wireless network;

The selecting unit is configured to select an LTE-U user with the smallest bandwidth as the LTE-U user Cell i to be cooperating with the 802.11 user.
The spectrum access device according to claim 6 or 7, wherein the variable calculation module comprises:

An extracting unit, configured to extract (m-1) group 802.11 users WLAN 1 to WLAN m-1 that are in different channels from the LTE-U user Cell i ;

a throughput calculation unit, configured to sequentially select a group of 802.11 users from the (m-1) group 802.11 users WLAN 1 to WLAN m-1 to access the LTE-U user cell in the LTE-U time period The i- th wireless channel where i is located, the throughput T ij , and the throughput attenuation amount D ij ;

Wherein, the throughput T ij is obtained when the jth group 802.11 user WLAN j accesses the ith radio channel where the LTE-U user Cell i is located in the LTE-U time period, and the 802.11 user WLAN j obtains The throughput attenuation D ij is the 802.11 when the ith 802.11 user WLAN j accesses the ith radio channel where the LTE-U user Cell i is located in the LTE-U time period. The throughput attenuation caused by the user WLAN j to the LTE-U user Cell i ; 1 ≤ j ≤ m-1.
The spectrum access device according to claim 8, wherein the spectrum assembling module comprises:

a balance variable calculation unit for calculating (m-1) balance variable values K 1 to K m-1 corresponding to the (m-1) group 802.11 users; wherein K j =T ij /D ij ;

The 802.11 user selection unit is configured to compare the (m-1) balance variable values K 1 to K m-1 , and set a group of 802.11 users with the largest balance variable value as the 802.11 user who can access the i th wireless channel. WLAN x ;

And a setting unit, configured to set the 802.11 user WLAN x to access the ith radio channel in the LTE-U time period.
The spectrum access device of claim 8, wherein the spectrum access module comprises:

a balance variable calculation unit for calculating (m-1) balance variable values K 1 to K m-1 corresponding to the (m-1) group 802.11 users; wherein K j =T ij /D ij ;

An attenuation amount screening unit, configured to select n groups of 802.11 users whose throughput attenuation is less than 13%;

An 802.11 user selection unit is configured to compare n balance variable values corresponding to the n groups of 802.11 users, and set a group of 802.11 users with the largest balance variable value as an 802.11 user WLAN x that can access the ith wireless channel;

And a setting unit, configured to set the 802.11 user WLAN x to access the ith radio channel in the LTE-U time period.