CN104717736B - A kind of LTE method for controlling downlink power and equipment - Google Patents

Abstract

The present invention discloses an LTE downlink power control method and device. The method includes: a base station eNB allocates transmit power to a radio element RE corresponding to a downlink physical downlink shared channel PDSCH channel; the eNB according to the service priority of the user equipment UE, and The position or link information of the UE adjusts the transmit power of the RE corresponding to the UE. In the present invention, the rationality of transmission power allocation is improved.

Description

A kind of LTE downlink power control method and device

technical field

The present invention relates to the field of communication technologies, and in particular, to an LTE downlink power control method and device.

Background technique

The main significance of downlink power control lies in: compensating for the path loss and shadow of the channel, reducing intra-cell and inter-cell interference, and reducing system energy consumption. The LTE (Long Term Evolution, Long Term Evolution) system adopts OFDMA (Orthogonal Frequency Division Multiple Access, Orthogonal Frequency Division Multiple Access) technology, therefore, to a certain extent, it can effectively eliminate the interference in the cell; LTE adopts RNTP (Relative Narrowband Tx Power, relative narrowband transmit power)/HII (High Interference Indication, high interference indication)/OI (Overload Indicator, overload indication) indication scheme achieves effective elimination of inter-cell interference; moreover, LTE pays more attention to the improvement of system capacity , that is, the system rate can be improved with a certain power. Based on the above three points, LTE adopts semi-static power allocation.

The LTE PDSCH (Physical Downlink Shared Channel, Physical Downlink Shared Channel) semi-static power allocation scheme is as follows:

The eNodeB (base station) determines the downlink transmission energy of each RE (Radio Element, radio element). The UE considers that the EPRE (EnergyPer RE, energy per radio element) of the downlink reference symbol is unchanged in the entire downlink system bandwidth and subframe until the power information referenceSignalPower (reference channel power) of different reference signals is received, and the value range is INTEGER (-60..50), which is a cell-specific parameter configured by higher layers.

For each UE (User Equipment user equipment), it is considered that the ratio of the EPRE of the data subcarrier in the PDSCH without the CRS (Cell Reference Signal, cell reference signal) to the EPRE of the CRS is represented by ρ _A :

ρ _A =δ _power-offset +P _A +10log ₁₀ (2)[dB]; 4 systems using diversity precoding scheme

ρ _A = δ _power-offset + P _A [dB]; other systems

Among them, PA is a UE-specific parameter semi-statically configured by the high layer, and its value range is [-6, _-4.77 ,-3,-1.77,0,1,2,3]dB.

For each UE, it is considered that the ratio of the EPRE of the data subcarrier in the PDSCH containing the CRS to the EPRE of the CRS is denoted by ρ _B , which can be calculated according to the following table:

Table 1. Cell-specific ρ _B /ρ _A

Among them, _PB is a cell-specific parameter configured by higher layers.

As shown above, in the semi-static power allocation scheme of the LTE downlink PDSCH, the EPRE of each RE of each PDSCH can be obtained according to referenceSignalPower, ρ _A and ρ _B .

It can be known from the expression of ρ _A that for each UE, there is only 9 dB of power adjustment space. Moreover, the current solution aims to improve the cell throughput rate, ignores the differences between UEs and services, and does not comprehensively consider factors such as UE type, location, and service characteristics during power allocation.

SUMMARY OF THE INVENTION

The present invention provides an LTE downlink power control method and device to improve the rationality of transmission power allocation.

In order to achieve the above purpose, the present invention provides a long-term evolution LTE downlink power control method, including:

The base station eNB allocates transmit power to the radio element RE corresponding to the downlink physical downlink shared channel PDSCH channel;

The eNB adjusts the transmit power of the RE corresponding to the UE according to the service priority of the user equipment UE and the position or link information of the UE.

An embodiment of the present invention also provides a base station eNB, including:

a power allocation module, configured to allocate transmit power to the radio element RE corresponding to the downlink physical downlink shared channel PDSCH channel;

The power adjustment module is configured to adjust the transmit power of the RE corresponding to the UE according to the service priority of the user equipment UE and the position or link information of the UE.

In the above embodiment of the present invention, after the NB allocates the transmit power to the REs corresponding to the downlink PDSCH channel, the NB adjusts the transmit power of the REs corresponding to the UE according to the service priority of the UE and the location or link information, and then determines the REs corresponding to the UE. When the transmit power is selected, the service characteristics and geographical location of the UE are comprehensively considered, which improves the rationality of transmit power allocation.

Description of drawings

FIG. 1 is a schematic flowchart of an LTE downlink power control method according to an embodiment of the present invention;

2 is a schematic diagram of a correspondence between a power offset value, a service priority of a UE, and a PL according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an eNB according to an embodiment of the present invention.

Detailed ways

In view of the problems existing in the above-mentioned prior art, an embodiment of the present invention provides a technical solution for LTE downlink power control. In this technical solution, after allocating the transmit power to the REs corresponding to the downlink PDSCH channel, the eNB adjusts the transmit power of the REs corresponding to the UE according to the service priority of the UE and the location or link information. When transmitting power, the service characteristics and geographical location of the UE are comprehensively considered, which improves the rationality of transmitting power allocation.

Wherein, the eNB may allocate the transmit power to the REs corresponding to the downlink PDSCH channel according to the existing power allocation model.

The technical solutions in the present application will be described clearly and completely below with reference to the accompanying drawings in the present application. Obviously, the described embodiments are a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present application.

As shown in FIG. 1, it is a schematic flowchart of an LTE downlink power control method provided by an embodiment of the present invention, which may include the following steps:

Step 101: The eNB allocates transmit power to REs corresponding to the downlink PDSCH channel.

Specifically, in the embodiment of the present invention, the eNB may perform power allocation to the REs corresponding to the downlink PDSCH channel according to the existing power allocation model, and the specific implementation thereof will not be repeated here.

Step 102: The eNB adjusts the transmit power of the RE corresponding to the UE according to the service priority of the UE and the location or link information of the UE.

Specifically, considering that different services may have different requirements for transmit power, and the influence of information such as the geographic location or link of the UE on the transmit power, in this embodiment of the present invention, in order to make the allocation of transmit power more reasonable, the eNB will After the RE corresponding to the downlink PDSCH channel is allocated to the UE, the transmit power of the RE corresponding to the UE (ie, the allocated RE) needs to be adjusted according to the service priority of the UE and the location or link information.

For example, for UEs with the same service priority in the eNB serving cell, the transmit power of the REs corresponding to the UE at the center can be reduced and the transmit power of the REs corresponding to the UE at the edge can be appropriately increased while ensuring the service rate.

Wherein, when the eNB adjusts the transmission power of the RE corresponding to the UE according to the service priority of the UE and the PL of the UE, it may first determine the transmission power of the RE corresponding to the UE according to the service priority of the UE and the position or link information of the UE. the power offset value of the power, and then offset the transmit power of the RE corresponding to the UE according to the power offset value.

Preferably, in the embodiment of the present invention, the eNB offsets the transmit power of the RE corresponding to the UE according to the power offset value, which can be specifically implemented by the following formula:

P*=P+△P;

Among them, P* is the transmit power of the REs corresponding to the UE after the offset, P is the transmit power of the REs corresponding to the UE before the offset, and ΔP is the power offset value.

In the embodiment of the present invention, the corresponding relationship between the power offset value and the service priority of the UE, and the location or link information can be preset. When the transmission power needs to be adjusted, it can be queried according to the service priority of the UE and the PL. The correspondence is to determine the power offset value of the transmit power of the RE corresponding to the UE;

Preferably, in this embodiment of the present invention, the location or link information of the UE may be a PL (PathLoss, path loss) of the UE, where:

When the service priorities are the same, the larger the PL of the UE, the larger the power offset value of the transmit power of the UE corresponding to the RE;

When the PL is the same, the higher the service priority of the UE is, the larger the power offset value of the transmit power of the RE corresponding to the UE is.

It should be noted that, in this embodiment of the present invention, when the UE bears multiple services, the eNB may, according to the service priority of the service with the highest service priority among the multiple services, and the location or link information of the UE, determine the The transmit power of the RE corresponding to the UE is adjusted.

In order to better understand the technical solutions provided by the embodiments of the present invention, the technical solutions provided by the embodiments of the present invention are described in more detail below with reference to specific application scenarios.

In this embodiment, the service priority is characterized by QCI (Quality of Service (QoS) ClassIdentifier, QoS class identifier); the location or link information of the UE is characterized by PL, and the power offset value (Offset) The value range is (-5, +5), and the PL value range is (0, 30); the corresponding relationship between the power offset value, the service priority of the UE, and the PL can be seen in Figure 2.

As shown in Figure 2, the ordinate is Offset, and the range of change is -5 to +5; the abscissa is PL, and the range of change is 0 to 30. Take the service with QCI=1 as an example:

The function of its Offset setting is:

Offset=2/12*PL+3; (0＜PL＜12)

Offset=5 (12＜PL＜30)

Similarly, other QCIs are also a piecewise function.

According to the correspondence shown in FIG. 2, after the eNB allocates power to the REs corresponding to the downlink PDSCH channel according to the existing power allocation model, when the power allocation needs to be adjusted, it can be adjusted according to the service priority of the UE (in this embodiment) It is characterized by QCI), and the PL query of the UE determines the corresponding power offset value (Offset), and then according to the power offset value, the occurrence power of the RE corresponding to the UE is offset.

For example, assuming that QCI=1 and PL=6 of the UE, according to the corresponding relationship shown in FIG. 2, it can be determined that the power offset value corresponding to the UE is Offset=2/12*PL+3=4, then the corresponding power offset value of the UE can be determined as Offset=2/12*PL+3=4. The transmit power after the RE offset is P*=P+4 (the transmit power of the RE corresponding to the UE is increased).

In this embodiment, the power offset value corresponding to the high-level QCI (the smaller the QCI value, the higher the QCI level) is larger, and the power offset value corresponding to the low-level QCI is smaller; at the same time, when the PL is larger When , the corresponding power offset value is larger, on the contrary, the smaller the PL is, the smaller the corresponding power offset value is, or even a negative number, that is, the transmit power is reduced.

It should be noted that the correspondence between QCI, PL and Offset provided in this embodiment is only a specific implementation of the technical solution provided by the embodiment of the present invention, and does not limit the protection scope of the present invention, that is, when the QCI is the same, The relationship between Offset and PL is not limited to that shown by the straight line shown in FIG. 2 , and a curve method can also be used, as long as Offset is positively correlated with QCI and PL.

It can be seen from the above description that in this embodiment of the present invention, after the eNB allocates the transmit power to the REs corresponding to the downlink PDSCH channel, the eNB adjusts the transmit power of the REs corresponding to the UE according to the service priority of the UE and the location or link information. , when determining the transmit power of the RE corresponding to the UE, the service characteristics and geographical location of the UE are comprehensively considered, which improves the rationality of the transmit power allocation.

Based on the same technical idea, an embodiment of the present invention further provides an eNB, which can be applied to the above method embodiments.

As shown in FIG. 3, it is a schematic structural diagram of an eNB provided by an embodiment of the present invention, which may include:

The power allocation module 31 is used for allocating transmit power to the radio element RE corresponding to the downlink physical downlink shared channel PDSCH channel;

The power adjustment module 32 is configured to adjust the transmit power of the RE corresponding to the UE according to the service priority of the user equipment UE and the position or link information of the UE.

The power adjustment module 32 is specifically configured to determine the power offset value of the transmit power of the RE corresponding to the UE according to the service priority of the UE and the position or link information of the UE; The transmit power of the RE corresponding to the UE is offset.

The power adjustment module 32 is specifically configured to offset the transmit power of the RE corresponding to the UE according to the power offset value by using the following formula:

P*=P+△P;

Wherein, P* is the transmit power of the REs corresponding to the UE after offset, P is the transmit power of the REs corresponding to the UE before the offset, and ΔP is the power offset value.

Wherein, the position or link information of the UE is the path loss PL of the UE; wherein,

When the service priorities are the same, the larger the PL of the UE, the larger the power offset value of the transmit power of the RE corresponding to the UE;

When the PL is the same, the higher the service priority of the UE is, the larger the power offset value of the transmit power of the RE corresponding to the UE is.

Wherein, the power adjustment module 32 is specifically configured to, when the UE bears multiple services, according to the service priority of the service with the highest service priority among the multiple services, and the location or link information of the UE, The transmit power of the RE corresponding to the UE is adjusted.

From the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation Way. Based on such understanding, the technical solutions of the present invention essentially or the parts that contribute to the prior art can be embodied in the form of a software product, and the computer software product is stored in a storage medium and includes several instructions for making a A terminal device (which may be a mobile phone, a personal computer, a server, or a network device, etc.) executes the methods described in the various embodiments of the present invention.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (8)

1. A long-term evolution LTE downlink power control method, characterized in that, comprising: The base station eNB allocates transmit power to the radio element RE corresponding to the downlink physical downlink shared channel PDSCH channel; The eNB adjusts the transmit power of the RE corresponding to the UE according to the service priority of the user equipment UE and the position or link information of the UE; The eNB adjusts the transmit power of the RE corresponding to the UE according to the service priority of the UE and the location or link information of the UE, specifically: The eNB determines the power offset value of the transmit power of the RE corresponding to the UE according to the service priority of the UE and the position or link information of the UE; The eNB offsets the transmit power of the REs corresponding to the UE according to the power offset value. 2. The method of claim 1, wherein the eNB offsets the transmit power of the REs corresponding to the UE according to the power offset value, which is specifically implemented by the following formula: P*=P+△P; Wherein, P* is the transmit power of the REs corresponding to the UE after offset, P is the transmit power of the REs corresponding to the UE before the offset, and ΔP is the power offset value. 3. The method according to claim 2, wherein the location or link information of the UE is a path loss PL of the UE; wherein, When the service priorities are the same, the larger the PL of the UE, the larger the power offset value of the transmit power of the RE corresponding to the UE; When the PL is the same, the higher the service priority of the UE is, the larger the power offset value of the transmit power of the RE corresponding to the UE is. 4. The method according to claim 1, wherein the eNB adjusts the transmit power of the RE corresponding to the UE according to the service priority of the user equipment (UE) and the position or link information of the UE, specifically: : When the UE bears multiple services, the eNB transmits to the RE corresponding to the UE according to the service priority of the service with the highest service priority among the multiple services and the location or link information of the UE power is adjusted. 5. A base station eNB, comprising: a power allocation module, configured to allocate transmit power to the radio element RE corresponding to the downlink physical downlink shared channel PDSCH channel; a power adjustment module, configured to adjust the transmit power of the RE corresponding to the UE according to the service priority of the user equipment UE and the position or link information of the UE; The power adjustment module is specifically configured to determine the power offset value of the transmit power of the RE corresponding to the UE according to the service priority of the UE and the position or link information of the UE; The transmit power of the RE corresponding to the UE is offset. 6. The eNB according to claim 5, wherein the power adjustment module is specifically configured to offset the transmit power of the RE corresponding to the UE according to the power offset value by using the following formula: P*=P+△P; Wherein, P* is the transmit power of the REs corresponding to the UE after offset, P is the transmit power of the REs corresponding to the UE before the offset, and ΔP is the power offset value. 7. The eNB according to claim 6, wherein the location or link information of the UE is a path loss PL of the UE; wherein, When the service priorities are the same, the larger the PL of the UE, the larger the power offset value of the transmit power of the RE corresponding to the UE; When the PL is the same, the higher the service priority of the UE is, the larger the power offset value of the transmit power of the RE corresponding to the UE is. 8. The eNB of claim 5, wherein The power adjustment module is specifically configured to, when the UE bears multiple services, according to the service priority of the service with the highest service priority among the multiple services, and the location or link information of the UE, the The transmit power of the RE corresponding to the UE is adjusted.