CN106162896B

CN106162896B - Uplink resource allocation method

Info

Publication number: CN106162896B
Application number: CN201510209670.9A
Authority: CN
Inventors: 武卓; 刘建国; 孟艳; 王钧; 韩锋; 谷俊嵘; 沈钢
Original assignee: Alcatel Lucent SAS
Current assignee: Alcatel Lucent SAS
Priority date: 2015-04-28
Filing date: 2015-04-28
Publication date: 2020-03-17
Anticipated expiration: 2035-04-28
Also published as: CN106162896A

Abstract

A method for allocating uplink resources of a secondary cell for user equipment in a base station of an LTE communication system, wherein the secondary cell is an unlicensed carrier, the method comprises the following steps: the base station determines a first number P, wherein the first number P is the minimum number of uplink physical resource blocks allocated to the user equipment by the base station; the base station determines a second number L, and divides all uplink physical resource blocks of the secondary cell into L sets of the second number, wherein each set comprises the first number P of physical resource blocks; and the base station allocates at least one of the second number L of sets to a user equipment.

Description

Uplink resource allocation method

Technical Field

The present invention relates to the field of communications technologies, and in particular, to the field of wireless communications technologies.

Background

In the field of wireless communication, generally, a traditional deployment method is that a system operates in a licensed band (licenedband), that is, the whole spectrum resource is reserved for the system to use. Typically, LTE communication systems operate using licensed frequency bands.

However, as wireless services further increase, the capacity and frequency band requirements for wireless communication systems also increase. In this case, the licensed band resource of the LTE system is relatively insufficient. Therefore, one of the recent research hotspots in the LTE field is how to utilize the resources of the unlicensed frequency band to offload the high-speed data traffic. This scheme is called as an LTE (Long term evolution) in Unlicensed spectrum (LTE-U) system

For example, in a typical scenario, the LTE system uses the frequency bands of the WiFi system. I.e. the situation where cells of the LTE system and cells of the WiFi system at least partly co-exist in geographical location. In this case, if the LTE system can use the WiFi frequency band to perform traffic offloading at some high-load moments, it is obvious that the performance of the system can be greatly improved, thereby effectively coping with high-load application scenarios.

Obviously, under the coexistence of LTE and WiFi systems, it is the most direct choice to utilize the authorized carrier of LTE system to assist the Access of the unlicensed carrier of WiFi system, so that the Licensed-Assisted Access (LAA) has become a hot spot in the mobile communication field recently.

In the technical requirements of 3GPP for LAA, one of the points is to ensure that the transmission of each node can spread to a frequency band of at least 80% of the total unlicensed carrier, and the bandwidth of each unlicensed carrier is at least 5 MHz. This is easy for downlink transmission transmitted by a base station, but for uplink transmission transmitted from a User Equipment (UE), since transmission on an unlicensed carrier is generally bursty and the amount of data is not large, the above-mentioned requirement may not be met

Some adjustments must be made to the uplink resource allocation for the unlicensed carriers to allow greater spreading of the uplink resources allocated for use by the UEs. The high-traffic company accordingly proposes an uplink resource allocation method, which divides an uplink physical resource block (RB for short) of a cell where an unlicensed carrier is located into 10 interlaces, allocates all RBs to the 10 interlaces uniformly, and allocates a certain interlace to a UE when uplink resource allocation is performed on the UE, thereby ensuring that RBs used by the UE are distributed in the whole frequency band from a scattered manner. For example, for a slave cell of a certain unlicensed carrier, assuming that there are 100 RBs, 10 RBs are contained in each interlace, i.e., the RB bit contained in the interlace0 is {0, 10, 20.. 90}, and obviously, if the interlace0 is allocated to a certain UE, the spreading requirement is satisfied.

This method, while satisfactory for distribution, has certain disadvantages. Firstly, if the number of interlaces is fixed, it means that the number of RBs included in each interlace is also fixed for a certain cell, which is not favorable for the base station to perform flexible scheduling, for example, in the above example, if the uplink of a certain UE does not need to use 10 RBs, but the base station can still only allocate one interlace, i.e. 10 RBs, it will inevitably cause waste of uplink resources; a more serious problem is that the unlicensed carrier used by the slave cell is not exclusively owned by the base station, and other neighboring cells may also attempt to use the unlicensed carrier at the same time, and if the Listen-before-talk (LBT) detection of the neighboring cell fails, the neighboring cell may also allocate uplink resources of the slave cell to another UE at the same time. Assuming that the neighboring cell also allocated interlace0 for another UE, then both UEs would transmit using exactly the same RB, causing extremely severe interference. In case all base stations use the same fixed interlace number, the probability of this interference occurring is considerable and must be addressed.

Therefore, the present invention aims to find a new uplink resource allocation method for the slave cell; this approach needs to enable the uplink resource allocation to meet the requirement of spreading; and to avoid inter-cell interference as much as possible after an LBT detection error.

Disclosure of Invention

In order to solve the above problems in the prior art, the present invention provides a new method for allocating uplink resources from a secondary cell. The base station determines how many RBs are contained in each interlace, so that the number of interlaces determined by different base stations is different. Thereby ensuring that the uplink resources allocated by different base stations do not coincide even if the LBT detection is erroneous.

Specifically, according to a first aspect of the present invention, a method for allocating uplink resources to a slave cell for a user equipment in a base station of an LTE communication system is provided, where the slave cell is an unlicensed carrier, and the method includes: the base station determines a first number P, wherein the first number P is the minimum number of uplink physical resource blocks allocated to the user equipment by the base station; the base station determines a second number L, and divides all uplink physical resource blocks of the secondary cell into L sets of the second number, wherein each set comprises the first number P of physical resource blocks; and the base station allocates at least one of the second number L of sets to a user equipment.

Preference is given toWherein, in step b, further comprising: when in use

When not divisible by P, the second quantity L is determined according to the following equation:

when in use

When divisible by P, the second quantity L is determined according to the following equation:

wherein the content of the first and second substances,

representing the number of all uplink physical resource blocks of the secondary cell,

representing an integer division operation.

More preferably, step b further includes determining the location of the uplink physical resource block in the ith set of the second number L of sets according to the following formula:

{l，l+L，l+2L，...，l+(P-1)L}

wherein L is more than or equal to 0 and less than or equal to L-1.

Preferably, the method further includes determining the position of the uplink physical resource block in the 11 th set of the second number L of sets by using an interleaver function, where L is greater than or equal to 0 and less than or equal to L-1.

More preferably, wherein the interleaver function used is an S-random interleaver.

Preferably, the method further comprises the following steps: and the base station sends a first message to the user equipment in a main cell, wherein the first message is used for indicating the result of the uplink resource allocation.

Preferably, the method further comprises the following steps: determining the first number P based on a cell identity of the base station.

Preferably, the method further comprises the following steps: determining the first number P based on an operator identity of the base station.

Preferably, the method further comprises the following steps: the first number P is determined by configuration by an operator of the base station.

According to a second aspect of the present invention, an apparatus for allocating uplink resources to a slave cell for a user equipment in a base station of an LTE communication system is provided, where the slave cell is an unlicensed carrier, and the apparatus includes: a first determining module, configured to determine a first number P by the base station, where the first number P is a minimum number of uplink physical resource blocks allocated to the user equipment by the base station; a second determining module, configured to determine a second number L by the base station, and divide all uplink physical resource blocks of the secondary cell into L sets of the second number, where each set includes P physical resource blocks of the first number; and an allocation module, configured to allocate, by the base station, at least one set of the second number L of sets to a user equipment.

Preferably, the second determining module is further configured to: when in use

when in use

wherein the content of the first and second substances,

representing an integer division operation.

More preferably, the second determining module is further configured to determine the location of the uplink physical resource block in the ith set of the second number L of sets according to the following formula:

{l，l+L，l+2L，...，l+(P-1)L}

wherein L is more than or equal to 0 and less than or equal to L-1.

Preferably, the second determining module is further configured to determine the location of the uplink physical resource block in the ith set of the second number L of sets by using an interleaver function, where L is greater than or equal to 0 and less than or equal to L-1.

Preferably, the allocating module is further configured to send, by the base station, a first message to the user equipment in a primary cell, where the first message is used to indicate a result of the uplink resource allocation.

Preferably, the first determining module is further configured to: determining the first number P based on a cell identity of the base station.

Preferably, the first determining module is further configured to: determining the first number P based on an operator identity of the base station.

Preferably, the first determining module is further configured to: the first number P is determined by configuration by an operator of the base station.

In the invention, the base station respectively determines the number of RBs contained in each interlace, thereby ensuring that uplink resources allocated by different base stations are not overlapped, and ensuring that the inter-cell interference can be reduced even under the condition of error detection of LBT; the requirement of fully distributing the uplink RB is ensured by a method of carrying out resource distribution by taking interlace as a unit; and in the preferred scheme, the configuration can be carried out by an operator, so that the requirement of flexible configuration is met, the waste of resources is effectively reduced, and the aim of the invention is fulfilled.

Drawings

Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments thereof, which proceeds with reference to the accompanying drawings.

Fig. 1 shows a flow chart of a method for allocating uplink resources from a cell for a user equipment in a base station of an LTE communication system according to the present invention;

fig. 2 shows a block diagram of an apparatus for allocating uplink resources from a cell to a user equipment in a base station of an LTE communication system according to the present invention;

wherein the same or similar reference numerals indicate the same or similar step features or means/modules.

Detailed Description

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof. The accompanying drawings illustrate, by way of example, specific embodiments in which the invention may be practiced. The illustrated embodiments are not intended to be exhaustive of all embodiments according to the invention. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

First, according to an application scenario of the present invention, there is an area covered by an LTE communication system, which includes at least one base station, i.e., eNB1, and one UE, i.e., UE1, and a licensed carrier, i.e., Primary Cell (Pcell), contacting the two. In addition, other unlicensed carriers exist in the area, which may also be used by other LTE or WiFi communication systems.

At a necessary time, the eNB1 uses the unlicensed carrier as a Secondary Cell (Scell). Therefore, eNB1 needs to allocate uplink resources on the Scell for UE1 to use for its uplink transmission. Based on the allocation method of the present invention, at this time, the eNB1 first determines the size of each interlace, i.e., how many RBs are included in each interlace, and the value is represented by P, which means the minimum number of uplink RBs that the eNB1 needs to allocate to the UE 1. And secondly, based on the P and the whole bandwidth of the Scell, the eNB1 determines how many interlaces need to be allocated to the Scell, the numerical value is represented by L, and then all uplink RBs on the Scell are allocated to the L interlaces. Thirdly, the eNB1 allocates uplink resources for the UE1 in units of interlaces, and may allocate uplink resources of one or more interlaces for the UE1 according to actual service requirements. The method for allocating uplink resources of the invention is realized through the three steps.

The present invention is based on the above aspect, and further provides that, in the second step: when in use

when in use

wherein the content of the first and second substances,

represents the number of all uplink RBs from the cell,

representing an integer division operation. For example, when there are 100 uplink RBs on the Scell, if P determined by eNB1 is 10, L is 10; if P is 8 as determined by eNB1, L is 13. It is obvious that when different base stations determine different P values, the L value will change instead of a fixed number, which is a significant difference between the present invention and the scheme of the koutou corporation.

Preferably, in the second step, the following two methods may be used to allocate all uplink RBs on the Scell to L interlaces.

The first method can use uniform allocation, that is, RBs are allocated to L interlaces one by one in sequence, that is, the position of the uplink RB in the ith interlace can be expressed as the following formula:

{l，l+L，l+2L，...，l+(P-1)L}

wherein L is more than or equal to 0 and less than or equal to L-1.

For example, when

When P is 10 and L is 10, the RB position included in the 0 th interlace is {0, 10, 20.., 90 }; when in use

When P is 8 and L is 13, the RB position included in the 0 th interlace is {0, 13, 26.., 91 }; it can be seen that the RB positions contained in the same numbered interlace are very different in the two cases, which means that even when LBT detection is wrong and two enbs allocate the resources of the unlicensed carrier at the same time, the interference can be greatly reduced as long as the respective determined P values are different. And this method is very simple beforehand.

The second method can use non-uniform allocation, that is, the interleaver function is used to determine the position of the uplink physical resource block in the first set, where L is greater than or equal to 0 and less than or equal to L-1. This has the advantage that the randomness of the distribution can be further ensured, so that even in the case where the P values are the same, the overlap of RB allocations can be reduced. It should be noted that various existing interleaver functions are applicable to the method, as long as the interleaved result can meet the scattering requirement. Without loss of uniqueness, an S random interleaver may be used, where S may be, for example, in a range of values

The benefit of this value is to ensure fast convergence of the results.

The present invention is based on the above solution and further proposes that, in the third step, a first message may be sent by the eNB1 to the UE1 on the Pcell for indicating the result of the above resource allocation, which may be the P value determined by the eNB1 and the l value allocated to the UE1 (corresponding to a uniform allocation), or directly the location of a group of RBs (corresponding to a non-uniform allocation) or any other information that may make the UE1 understand the allocation result. For example, the transmission may be performed using layer 1 or higher layer messages.

The present invention is based on the above solution, and further proposes that, in the first step, the P value can be determined using several methods as follows.

For example, the P value may be implicitly determined using a Cell identification (Cell ID) of eNB 1. That is, different P values corresponding to different Cell IDs may be defined in advance. The method is suitable for the situation that different base stations under the same operator flag can share one unlicensed carrier frequency band.

As another example, the P value may be implicitly determined using an operator ID (operator ID) of the eNB 1. That is, different P values corresponding to different operator IDs can be defined in advance. The operator ID may be represented by the PLMN or EARFCN of the licensed carrier when the unlicensed carrier is aggregated with the licensed carrier. This approach is suitable for the situation where base stations under different operator flags may share one unlicensed carrier band.

Yet another approach is that the P value may be manually configured by the operator of eNB1, which is mainly applicable to scenarios where flexible configuration is often required.

Fig. 1 shows a flow chart of activating Scell according to the above embodiment, including:

s11, the base station determines a first quantity P, wherein the first quantity P is the minimum quantity of uplink physical resource blocks allocated to the user equipment by the base station;

s12, the base station determines a second number L, and divides all uplink physical resource blocks of the secondary cell into L sets of the second number, wherein each set comprises the first number P of physical resource blocks; and

s13, the base station allocates at least one set in the second quantity L sets to the user equipment.

The following describes the apparatus corresponding to the above method provided by the present invention with reference to the drawings, and the unit/device features thereof are corresponding to the step features in the above method, which will be simplified.

Fig. 2 shows an apparatus 20 for allocating uplink resources to a secondary cell for a user equipment in a base station of an LTE communication system, wherein the secondary cell is an unlicensed carrier, the apparatus comprising:

a first determining module 2001, configured to determine a first number P by the base station, where the first number P is a minimum number of uplink physical resource blocks allocated to the ue by the base station;

a second determining module 2002, configured to determine a second number L, and divide all uplink physical resource blocks of the secondary cell into L sets of the second number, where each set includes P physical resource blocks of the first number;

an allocating module 2003 for allocating at least one of the second number L of sets to a user equipment by the base station.

While embodiments of the present invention have been described above, the present invention is not limited to a particular system, device, and protocol, and various modifications and changes may be made by those skilled in the art within the scope of the appended claims.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art from a study of the specification, the disclosure, the drawings, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. In the present invention, "first" and "second" merely indicate names and do not represent order relationships. In practical applications of the invention, one element may perform the functions of several technical features recited in the claims. Any reference signs in the claims shall not be construed as limiting the scope.

Claims

1. A method for allocating uplink resources of a secondary cell for user equipment in a base station of an LTE communication system, wherein the secondary cell is an unlicensed carrier, the method comprises the following steps:

a. the base station determines a first number P, wherein the first number P is the minimum number of uplink physical resource blocks allocated to the user equipment by the base station;

b. the base station determines a second number L, and divides all uplink physical resource blocks of the secondary cell into L sets of the second number, wherein each set comprises the first number P of physical resource blocks; and

c. the base station allocates at least one of the second number L of sets to a user equipment.

2. The method according to claim 1, wherein in step b further comprising,

when in use

when in use

wherein the content of the first and second substances,

represents whole divisionAnd (6) operation.

3. The method according to claim 2, wherein step b further comprises determining the location of the uplink physical resource block in the ith set of the second number L of sets according to the following formula:

{l，l+L，l+2L，…，l+(P-1)L}

wherein L is more than or equal to 0 and less than or equal to L-1.

4. The method according to claim 2, wherein step b further comprises determining the position of the uplink physical resource block in the first set of the second number L of sets using an interleaver function, wherein 0 ≦ L ≦ L-1.

5. The method of claim 4, wherein the interleaver function used is an S-random interleaver.

6. The method of claim 1, wherein the step c further comprises:

and the base station sends a first message to the user equipment in a main cell, wherein the first message is used for indicating the result of the uplink resource allocation.

7. The method of claim 1, wherein the step a further comprises:

determining the first number P based on a cell identity of the base station.

8. The method of claim 1, wherein the step a further comprises:

determining the first number P based on an operator identity of the base station.

9. The method of claim 1, wherein the step a further comprises:

the first number P is determined by configuration by an operator of the base station.

10. An apparatus for allocating uplink resources of a slave cell to a user equipment in a base station of an LTE communication system, wherein the slave cell is an unlicensed carrier, the apparatus comprising:

a first determining module, configured to determine a first number P by the base station, where the first number P is a minimum number of uplink physical resource blocks allocated to the user equipment by the base station;

a second determining module, configured to determine a second number L by the base station, and divide all uplink physical resource blocks of the secondary cell into the second number L of sets, where each set includes the first number P of physical resource blocks; and

an allocating module, configured to allocate, by the base station, at least one set of the second number L of sets to a user equipment.

11. The device of claim 10, wherein the second determination module is further configured to:

when in use

when in use

wherein the content of the first and second substances,

representsThe number of all uplink physical resource blocks of the secondary cell,

representing an integer division operation.

12. The device of claim 11, wherein the second determining module is further configured to determine the location of the uplink physical resource blocks in the ith set of the second number L of sets according to the following formula:

{l，l+L，l+2L，…，l+(P-1)L}

wherein L is more than or equal to 0 and less than or equal to L-1.

13. The apparatus of claim 10, wherein the second determining module is further configured to determine the location of the uplink physical resource blocks in the first set of the second number L of sets using an interleaver function, wherein 0 ≦ L-1.

14. The apparatus of claim 13, wherein the interleaver function used is an S-random interleaver.

15. The device of claim 10, wherein the allocating module is further configured to send, by the base station, a first message to the user equipment in a primary cell, wherein the first message is used to indicate a result of the uplink resource allocation.

16. The device of claim 10, wherein the first determination module is further to:

determining the first number P based on a cell identity of the base station.

17. The device of claim 10, wherein the first determination module is further to:

18. The device of claim 10, wherein the first determination module is further to: