WO2017113801A1

WO2017113801A1 - Method and device for transmitting downlink data of cell

Info

Publication number: WO2017113801A1
Application number: PCT/CN2016/093992
Authority: WO
Inventors: 毛凯
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-12-28
Filing date: 2016-08-08
Publication date: 2017-07-06
Also published as: CN106922003A

Abstract

The present invention provides a method and device for transmitting downlink data of a cell, the method comprising: calculating, according to a coverage area of a designated cell, a first downlink transmission bandwidth of the cell; and transmitting downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth. The present invention provides a method of increasing the coverage area of a cell, resolving the problems in the related art of an increase in RRU costs and inflexible transmission bandwidth resulting from the coverage area of the cell being increased by decreasing RRU supported protocol bandwidth.

Description

Method and device for transmitting downlink data of cell

Technical field

The present invention relates to the field of communications, and in particular to a method and an apparatus for transmitting downlink data of a cell.

Background technique

The long-term evolution technology (Long Time Evolution, LTE for short) is mainly for indoor and outdoor macro coverage. The radio remote unit (RRU) has limited power and limited cell coverage. For the coverage scenarios such as mountainous areas or Gobi, the main characteristics of user distribution are large scope and low density. If the existing products are used to build networks, the coverage can only be increased by adding stations, which will undoubtedly increase the cost of operators.

In the current LTE system, if the cell coverage is to be increased, the only way to limit the bandwidth of the RRU is to support a smaller protocol bandwidth. This requires the RRU to support multiple bandwidths at the same time. However, the related art method will bring many disadvantages at the same time. First, this will bring about an increase in the cost of the RRU. Secondly, the actual transmission bandwidth of the RRU is not flexible enough to be adjusted as needed.

For the related art, the technical problem of the RRU support protocol bandwidth must be adjusted when the cell coverage is increased. No effective solution has been found, and no other method for increasing the cell coverage is found when the cell parameters are unchanged. .

Summary of the invention

The embodiment of the invention provides a method and a device for transmitting downlink data of a cell, which solves the problem that the RRU cost is increased and the transmission bandwidth is inflexible when the cell coverage is increased by reducing the protocol bandwidth supported by the RRU in the related art. The problem.

According to an embodiment of the present invention, a method for transmitting downlink data of a cell is provided, including: calculating a first downlink transmission bandwidth of the cell according to a specified cell coverage; and transmitting, at the first downlink transmission bandwidth, The downlink data of the cell is transmitted on the frequency band resource.

In the embodiment of the present invention, calculating the first downlink transmission bandwidth of the cell according to the specified cell coverage, including: acquiring the specified cell coverage; and calculating to send the coverage on the specified cell coverage The path loss of the downlink data; the first downlink transmission bandwidth is obtained according to the path loss calculation.

In the embodiment of the present invention, calculating the first downlink transmission bandwidth according to the path loss includes: calculating the first downlink transmission bandwidth BW _Tx according to the following formula:

The Num _p is the number of ports of the cell, the Num _sc is the number of subcarriers on each RB to be sent downlink data, and the RRU _pwr is the rated transmit power of the cell, the ρ _A is an offset value of the first type of service symbol relative to the reference signal power, the ρ _B is an offset value of the second type of service symbol relative to the reference signal power, and the reference signal power RS _pwr =RSRP _min +PL, The RSRP _min is a minimum reception level of the cell, and the PL is a path loss for transmitting the downlink data.

In the embodiment of the present invention, the sending the downlink data of the cell on the frequency domain resource of the first downlink transmission bandwidth includes: determining whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where The minimum bandwidth constraint includes a bandwidth occupied by a physical broadcast channel PBCH; and when the transmission bandwidth is greater than or equal to a minimum bandwidth constraint, transmitting downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth. .

In the embodiment of the present invention, before the downlink data of the cell is sent on the frequency band resource of the first downlink transmission bandwidth, the method further includes: determining whether the downlink data includes both broadcast data and user data; When the downlink data includes the broadcast data and the user data, preferentially allocate a first frequency band resource for transmitting the broadcast data from the frequency band resource; after the first frequency band resource allocation is completed, A second band resource for transmitting the user data is allocated among remaining resources of the band resource.

In the embodiment of the present invention, the transmitting the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth includes: determining, in the specified resource block RB, the first corresponding to the first downlink transmission bandwidth RB; initializing a resource bitmap of the frequency band resource according to the first RB, where a bit of the resource bitmap corresponds to the designated RB, and the value of the bit is used to indicate: Whether the RB corresponding to the bit is the first RB, whether the first RB is occupied, and the service type of the downlink data occupying the first RB; according to the resource bitmap and the service type, The first RB is allocated to the downlink data, and the resource bitmap is updated according to the result of the allocation; and the downlink data of the corresponding service type is sent on the first RB.

According to another embodiment of the present invention, there is provided a device for transmitting downlink data of a cell, comprising: a calculating module, configured to calculate a first downlink transmission bandwidth of the cell according to a specified cell coverage; a sending module, setting And transmitting downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth.

In the embodiment of the present invention, the calculating module includes: an acquiring unit, configured to acquire the specified cell coverage; the first calculating unit is configured to calculate, by using the specified cell coverage, the downlink data The second calculation unit is configured to calculate the first downlink transmission bandwidth according to the path loss.

In the embodiment of the present invention, the second calculating unit is configured to calculate the first downlink transmission bandwidth BW _Tx according to the following formula:

In the embodiment of the present invention, the sending module further includes: a determining unit, configured to determine whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where the minimum bandwidth constraint includes a physical broadcast channel PBCH The occupied bandwidth is configured to: when the transmit bandwidth is greater than or equal to the minimum bandwidth constraint, send downlink data of the cell on the frequency resource of the first downlink transmit bandwidth.

In the embodiment of the present invention, the device further includes: a determining module, configured to: before the transmitting module sends the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth, determine whether the downlink data is Simultaneously including broadcast data and user data; the first allocating module is configured to: when the downlink data includes the broadcast data and the user data, preferentially allocate a first part for transmitting the broadcast data from the frequency band resource a frequency band resource; the second allocation module is configured to allocate, after the first frequency band resource allocation is completed, a second frequency band resource for transmitting the user data from remaining resources of the frequency band resource.

In the embodiment of the present invention, the sending module further includes: a selecting unit, configured to select a first RB corresponding to the first downlink transmission bandwidth in the designated resource block RB; and an initializing unit, configured to be according to the a first RB, a resource bitmap of the frequency band resource is initialized, wherein a bit of the resource bitmap corresponds to the designated RB, and a value of the bit is used to indicate: an RB corresponding to the bit Whether it is the first RB, whether the first RB is occupied, and a service type that occupies the downlink data of the first RB; and the processing unit is configured to: according to the resource bitmap and the service type, The first RB is allocated to the downlink data, and the resource bitmap is updated according to the result of the allocation; and the sending unit is configured to send the downlink data of the corresponding service type on the first RB.

In the embodiment of the present invention, a computer storage medium is further provided, and the computer storage medium may store an execution instruction, where the execution instruction is used to perform the process of sending the downlink data of the cell in the foregoing embodiment.

According to the embodiment of the present invention, the first downlink transmission bandwidth of the cell is calculated according to the specified cell coverage, and the downlink data of the cell is sent on the frequency resource of the first downlink transmission bandwidth, without changing. On the premise of the cell bandwidth parameter, the cell coverage is increased according to actual needs, and the first downlink transmission bandwidth of the current cell coverage is calculated, and the limited power resources are concentrated on the band resources of the first downlink transmission bandwidth. The data increases the transmission power of the unit bandwidth, thereby providing a method for increasing the coverage of the cell, and solving the RRU caused by increasing the coverage of the cell by reducing the protocol bandwidth supported by the RRU in the related art. The problem of increased cost and inflexible transmission bandwidth.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a flowchart of a method for transmitting downlink data of a cell according to an embodiment of the present invention;

2 is a structural block diagram of a device for transmitting downlink data of a cell according to an embodiment of the present invention;

3 is a block diagram 1 of an optional structure of a device for transmitting downlink data of a cell according to an embodiment of the present invention;

4 is a block diagram 2 of an optional structure of a device for transmitting downlink data of a cell according to an embodiment of the present invention;

5 is a block diagram 3 of an optional structure of a device for transmitting downlink data of a cell according to an embodiment of the present invention;

6 is a structural block diagram of a transmitting module in a device for transmitting downlink data of a cell according to an embodiment of the present invention;

7 is a schematic diagram of a system for transmitting downlink data of a cell according to an alternative embodiment of the present invention;

8 is a flowchart showing the operation of a parameter management module according to an alternative embodiment of the present invention;

9 is a flowchart showing the operation of a band resource management module according to an alternative embodiment of the present invention;

10a, 10b, and 10c are schematic diagrams of band resource bitmap markers in accordance with an alternate embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It is to be understood that the terms "first", "second" and the like in the specification and claims of the present invention are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

In this embodiment, a method for transmitting downlink data of a cell is provided. FIG. 1 is a flowchart of a method for transmitting downlink data of a cell according to an embodiment of the present invention. As shown in FIG. 1, the process includes the following steps:

Step S102: Calculate a first downlink transmission bandwidth of the cell according to the specified cell coverage range.

Step S104: Send downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth.

Optionally, the specified cell coverage may be determined according to user settings, and the current coverage of the cell may be expanded or reduced. When the current coverage of the cell is expanded to a specified cell coverage, the downlink data may be transmitted. In the coverage of the specified cell, since the bandwidth parameter of the cell does not need to be considered in this embodiment, the available power resources of the cell are unchanged. By reducing the downlink transmission bandwidth of the cell, the allocated transmit power per unit bandwidth will be When the downlink data is transmitted, the bandwidth of the band resource can be transmitted further, so that users outside the original cell coverage can also access and obtain the cell service. Optionally, the downlink data may be broadcast data or user data.

In this embodiment, the first downlink transmission bandwidth of the cell is calculated according to the specified cell coverage, and the downlink data of the cell is sent on the frequency component of the first downlink transmission bandwidth. In this embodiment, the cell bandwidth is not changed. On the premise of the parameter, the cell coverage is increased according to the actual needs, and the first downlink transmission bandwidth of the current cell coverage is calculated, and the downlink data is transmitted by concentrating the limited power resources to the band resources of the first downlink transmission bandwidth. The transmission power of the unit bandwidth is increased, thereby providing a method for increasing the coverage of the cell, and solving the RRU cost increase caused by increasing the coverage of the cell by reducing the protocol bandwidth supported by the RRU in the related art. Big and emission bandwidth is not flexible.

In an optional implementation manner of this embodiment, calculating, according to the specified cell coverage, a first downlink transmission bandwidth of the cell, including:

S11. Acquire a specified cell coverage range.

S12. Calculate a path loss for transmitting downlink data on a specified cell coverage area.

S13. Calculate the first downlink transmission bandwidth according to the path loss.

Optionally, in the process of specifically calculating the first downlink transmission bandwidth, the following process may be used to derive and calculate:

This embodiment can be applied to the scenario of an LTE network. In an LTE scenario, the transmit power of each downlink orthogonal frequency division multiplexing (OFDM) symbol cannot exceed the rated transmit power of the cell RRU. This alternative embodiment derives the available first downlink transmit bandwidth by the RRU's nominal transmit power and the acquired cell coverage. According to the information category carried by the downlink transmission bandwidth, the downlink OFDM symbols can be classified into two categories: service symbols and control symbols.

Optionally, the service symbol may be classified into a first type (including a reference signal) symbol and a second type (without a reference signal) symbol according to whether the service symbol includes reference information. The transmit power of the service symbol is the reference signal power RS _pwr , the number of reference signals Num _p on a resource block (RB), the offset of the first type of symbol relative to the reference signal power ρ _A or the second type The offset ρ _{B of the} symbol with respect to the reference signal power, the number of subcarriers N ux _sc per RB, and the maximum transmission bandwidth BW _Tx (in RB) are determined. The maximum transmit power Tx _{max_pwr} of the service symbol depends on the maximum transmit power between the first type and the second type of symbols, and the corresponding calculation formula is as follows:

Formula constraint relationship, the maximum transmit power of traffic symbol can not exceed the nominal transmit power cell RRU RRU _PWR, _namely: RRU _pwr ≥Tx max_pwr, when the _RRU _pwr = Tx max_pwr, may tear down the first downlink transmission bandwidth:

In the formula for deriving the first downlink transmission bandwidth, all parameters except the reference signal power RS _pwr are known, Num _{p is} determined by the number of cell ports, and Num _sc is for each RB of the downlink data to be transmitted. The number of subcarriers, ρ _A is the offset value of the first type of service symbol relative to the reference signal power, ρ _B is the offset value of the second type of service symbol relative to the reference signal power, and ρ _A and ρ _B may be according to the user The input data is configured, and the reference signal power can be calculated by adding the cell minimum reception level RSRP _min and the path loss PL (Path Loss): that is, RS _pwr =RSRP _min +PL.

The minimum reception level RSRP _min of the cell is a known parameter of the cell. Optionally, the path loss PL can be obtained according to a given cell coverage through a link budget. The actual minimum transmission bandwidth BW _{Tx_min} cannot be smaller than the number of RBs occupied by the Physical Broadcast Channel (PBCH). According to the above derivation relationship, the maximum coverage of the cell supported by the RRU of the cell can be obtained.

In this embodiment, the power of the control symbol cannot exceed the rated transmit power of the RRU. The control symbol is located in the first few symbols of the LTE time-frequency resource, and is used to carry bit information of a physical downlink control channel (Physical Downlink Control Channel, PDCCH for short). Since the bits of the PDCCH are discretely distributed on all control symbols, the specific location may not be set. In order to prevent the control symbol power from exceeding the RRU rated power, the number of control symbols can be set to a maximum value. Ensure that the number of PDCCH bits on each control symbol is balanced.

In an optional implementation manner of this embodiment, the sending the downlink data of the cell on the frequency domain resource of the first downlink transmission bandwidth includes:

S21. Determine whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where the minimum bandwidth constraint includes a bandwidth occupied by the physical broadcast channel PBCH.

S22. When the transmission bandwidth is greater than or equal to the minimum bandwidth constraint, send downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth.

In the scenario of the LTE network, the PBCH information may be located in the middle of the protocol bandwidth, and the bandwidth resource location of the maximum transmission bandwidth may be limited to the middle of the protocol bandwidth, and the bandwidth resource location of the PBCH may be included. Therefore, it is ensured that when a subframe having a PBCH transmits data, there is no power overflow and the broadcast information cannot be transmitted. In this embodiment, the maximum transmission bandwidth under the coverage of a given cell is calculated by the constraint relationship between the rated power of the RRU and the actual transmit power, and the service data is restricted to be transmitted only within the actual transmission bandwidth, without changing the RRU rated transmit power and protocol. Under the premise of bandwidth parameters, the goal of expanding the coverage of the cell is achieved.

According to the foregoing optional implementation manner, when the downlink data includes the broadcast data and the user data, the priorities of the reserved frequency band resources are different, and the frequency band resources of the broadcast data may be reserved preferentially, specifically, the first downlink transmission bandwidth is Before transmitting the downlink data of the cell on the frequency band resource, the method further includes:

S31. Determine whether the downlink data includes both broadcast data and user data.

S32. When the downlink data includes the broadcast data and the user data, the first frequency band resource for transmitting the broadcast data is preferentially allocated from the frequency band resource;

S33. After the first frequency band resource allocation is completed, the second frequency band resource for transmitting the user data is allocated from the remaining resources of the frequency band resource.

In an optional implementation manner of this embodiment, there are multiple RBs for carrying downlink data on the frequency band resource, and the resource bitmap may be used to manage the frequency band resource, and the cell is sent on the frequency band resource of the first downlink transmission bandwidth. Downstream data includes:

S41, the first RB corresponding to the first downlink transmission bandwidth is determined in the designated resource block RB; optionally, the designated resource block RB is all RBs on the frequency band resource of the cell available bandwidth;

S42: Initialize a resource bitmap of the frequency band resource according to the first RB, where the bit of the resource bitmap corresponds to the designated RB, and the value of the bit is used to indicate whether the RB corresponding to the bit is the first RB, Whether an RB is occupied, and a service type occupying downlink data of the first RB;

S43. Assign, according to the resource bitmap and the service type, the first RB to the downlink data, and update the resource bitmap according to the allocated result;

S44. Send downlink data of a corresponding service type on the first RB.

Through the description of the above embodiments, those skilled in the art can clearly understand the square according to the above embodiments. The method can be implemented by means of software plus the necessary general hardware platform, of course, it can also be through hardware, but in many cases the former is a better implementation. Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a storage medium (such as ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a cell phone, a computer, a server, or a network device, etc.) to perform the methods of various embodiments of the present invention.

In this embodiment, a device for transmitting downlink data of a cell is also provided, and the device may be configured on the RRU of the cell base station, and the device is used to implement the foregoing embodiments and preferred embodiments, and details are not described herein. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

2 is a structural block diagram of a device for transmitting downlink data of a cell according to an embodiment of the present invention. As shown in FIG. 2, the device includes:

The calculating module 20 is configured to calculate a first downlink transmission bandwidth of the cell according to the specified cell coverage range;

The sending module 22 is configured to send downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth.

FIG. 3 is a block diagram of an optional structure of a device for transmitting downlink data of a cell according to an embodiment of the present invention. As shown in FIG. 3, the computing module 20 includes:

The obtaining unit 30 is configured to obtain a specified cell coverage range;

The first calculating unit 32 is configured to calculate a path loss for transmitting downlink data on the specified cell coverage;

The second calculating unit 34 is configured to calculate the first downlink transmission bandwidth according to the path loss.

Optionally, the second calculating unit 34 may be configured to calculate the first downlink transmission bandwidth BW _Tx according to the following formula:

Num _p is the number of ports of the cell, Num _sc is the number of subcarriers on each RB to be sent downlink data, RRU _pwr is the rated transmit power of the cell, and ρ _A is the first type of service symbol relative to the reference signal power. The offset value, ρ _B is the offset value of the second type of service symbol relative to the reference signal power, and the reference signal power RS _pwr =RSRP _min +PL, where RSRP _min is the minimum reception level of the cell, and PL is the downlink data for transmission. Road damage.

FIG. 4 is a block diagram 2 of an optional structure of a device for sending downlink data of a cell according to an embodiment of the present invention. As shown in FIG. 4, the device includes, in addition to all the modules shown in FIG. 2, the sending module 22 further includes:

The determining unit 40 is configured to determine whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where the minimum bandwidth constraint includes a bandwidth occupied by the physical broadcast channel PBCH;

The determining unit 42 is configured to send the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth when the transmission bandwidth is greater than or equal to the minimum bandwidth constraint.

5 is a block diagram 3 of an optional structure of a device for transmitting downlink data of a cell according to an embodiment of the present invention, as shown in FIG. 5, The device includes, in addition to all the modules shown in FIG. 2, the device further includes:

The determining module 50 is configured to: before the sending module sends the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth, determine whether the downlink data includes the broadcast data and the user data at the same time;

The first allocating module 52 is configured to preferentially allocate a first frequency band resource for transmitting broadcast data from the frequency band resource when the downlink data includes the broadcast data and the user data;

The second allocation module 54 is configured to allocate a second frequency band resource for transmitting user data from the remaining resources of the frequency band resource after the first frequency band resource allocation is completed.

FIG. 6 is a structural block diagram of a sending module in a device for transmitting downlink data of a cell according to an embodiment of the present invention. As shown in FIG. 6, the sending module 22 further includes:

The selecting unit 60 is configured to select a first RB corresponding to the first downlink transmission bandwidth in the designated resource block RB;

The initializing unit 62 is configured to initialize a resource bitmap of the frequency band resource according to the first RB, where the bit of the resource bitmap corresponds to the designated RB, and the value of the bit is used to indicate whether the RB corresponding to the bit is the first An RB, whether the first RB is occupied, and a service type occupying downlink data of the first RB;

The processing unit 64 is configured to allocate the first RB to the downlink data according to the resource bitmap and the service type, and update the resource bitmap according to the allocated result;

The sending unit 66 is configured to send downlink data of the corresponding service type on the first RB.

The solution of the present invention will be described in detail below in conjunction with an alternative embodiment in accordance with the present invention:

The embodiment is used to adjust the downlink actual transmission bandwidth (corresponding to the first downlink transmission bandwidth) to adjust the limited power resources to the partial frequency band without changing the RRU transmission power and the configuration bandwidth. Large cell coverage.

The solution of this embodiment includes:

S51. Under LTE, the actual transmit power of each downlink OFDM symbol cannot exceed the rated transmit power of the RRU. The actual transmit bandwidth is derived from the nominal transmit power of the RRU and the given cell coverage. According to the type of information carried, the downlink OFDM symbols can be divided into two categories: service symbols and control symbols: the service symbols can be classified into a first type (including a reference signal) and a second type (without a reference signal) symbols. The transmit power of the service symbol is determined by the reference signal power RS _pwr , the number of reference signals N um _p per RB (Resource Block resource block), the offset ρ _{A of the} first type of symbol relative to the reference signal power, or the second type of symbol reference signal power offset ρ _B, the number of sub-carriers on each Num _sc RB and the actual emission bandwidth BW _Tx (RB units) determined. The maximum transmit power Tx _{max_pwr} of the service symbol depends on the maximum transmit power between the first type and the second type of symbols, and the corresponding calculation formula is as follows:

The constraint relationship is that the maximum transmit power of the service symbol cannot exceed the RRU's rated transmit power RRU _pwr . which is:

RRU _pwr ≥ _{Tx max_pwr} ;

When RRU _pwr =Tx _{max_pwr} ,

The actual emission bandwidth can be inversely calculated as:

In the formula, other parameters except the reference signal power RS _pwr are known, Num _{p is} determined by the number of cell ports, and Num _sc is the number of subcarriers on each RB of the downlink data to be transmitted, optionally, The number of subcarriers on the unit RB is 12, ρ _A and ρ _B are configurable, and the reference signal power can be calculated from the minimum reception level RSRP _min and the path loss PL (Path Loss path loss) of the cell:

RS _pwr =RSRP _min +PL,

The minimum reception level of the cell is a known parameter, and the path loss can be obtained according to the given cell coverage through the link budget. At the same time, the actual minimum transmission bandwidth BW _{Tx_min} cannot be smaller than the number of RBs (Resource Blocks) occupied by the PBCH (Physical Broadcast Channel), and according to the above derivation relationship, the maximum coverage of the cell that the RRU rated power can support can be obtained.

The power of the control symbol also cannot exceed the rated transmit power of the RRU. In this embodiment, the control symbol is located in the first few symbols of the LTE time-frequency resource, and is used to carry bit information of a PDCCH (Physical Downlink Control Channel). Since the bits of the PDCCH are discretely distributed on all control symbols, the specific location cannot be artificially set. In order to prevent the control symbol power from exceeding the RRU rated power, the number of control symbols can be set to a maximum value to ensure that the number of PDCCH bits on each control symbol is equalized.

S52. In this embodiment, the PBCH (Physical Broadcast Channel) information of the LTE is located at an intermediate position of the protocol bandwidth. Therefore, in the present embodiment, the band resource position of the actual transmission bandwidth is limited to the intermediate position of the protocol bandwidth, and the band resource location of the PBCH is included. This ensures that there is no power overflow when the PBCH subframe is transmitting data. In this embodiment, the entire protocol bandwidth is divided into bitmaps in units of RBs, and a flag of 1 indicates that the RB can be used. Otherwise, a value of 0 indicates that the RB is prohibited from being used.

According to the embodiment, the actual transmission bandwidth under the coverage of a given cell is calculated by the constraint relationship between the rated power of the RRU and the actual transmit power, and the service data is restricted to be transmitted only within the actual transmission bandwidth, without changing the RRU rated transmit power. Under the premise of the protocol bandwidth parameter, the purpose of expanding the coverage of the cell is achieved.

FIG. 7 is a schematic diagram of a system for transmitting downlink data of a cell according to an alternative embodiment of the present invention, which may be implemented on a base station processing unit (BBU) side of a base station, as shown in FIG. 7, including: a parameter management module 70, Band resource management module 72, wherein

The parameter management module 70 is configured to manage the settable parameters and determine an actual transmission bandwidth;

The band resource management module 72 is configured to determine an actual transmit band resource location and perform band resource allocation;

FIG. 8 is a flowchart showing the operation of a parameter management module according to an alternative embodiment of the present invention. As shown in FIG. 8, the method includes:

S801, setting input parameters, including path loss (obtained according to a given cell coverage range through a link budget), RRU rated power, cell minimum receiving level, number of cell ports, ρ _A , ρ _B , and simultaneously setting The number of control symbols is the maximum value specified by the protocol.

S802, determining whether the set value is within a limited range, if the range is exceeded, the prompt parameter setting is incorrect, and a reasonable value range is given.

S803, calculating an actual transmission bandwidth according to the set parameters:

S804, determining whether the transmission bandwidth meets a preset condition, and if the calculated actual transmission bandwidth does not satisfy the minimum bandwidth constraint condition, that is, less than the bandwidth occupied by the PBCH channel, the prompt parameter setting is unreasonable; if the actual transmission bandwidth is within a reasonable range, Execute S805;

S805, the parameter is transmitted to the band resource management module 72.

FIG. 9 is a flowchart of operation of a band resource management module according to an alternative embodiment of the present invention. As shown in FIG. 9, the method includes:

S901: Initialize a cell band resource bitmap BITMAP _Cell , and each RB corresponds to one bit position:

a. symmetrically expanding from the middle of the bandwidth to both sides to include the PBCH position until the number of RBs reaches the actual transmission bandwidth calculated by module 1;

b. The RB corresponding bit position of the actual transmission bandwidth is marked as 1, indicating that the RB can be used, the other RBs are marked as 0, indicating that the RB cannot be used, and the starting RB position of the actual transmission bandwidth is recorded as RB _Start .

10a, 10b, and 10c are schematic diagrams of a band resource bitmap in accordance with an alternative embodiment of the present invention. As shown in FIG. 10a, FIG. 10b, and FIG. 10c, in this embodiment, the background configuration bandwidth is 10M, and the 10M bandwidth is 10M. For the 50 RBs corresponding to the band resources, the actual transmission bandwidth calculated is 20 RBs, as shown in FIG. 10a, which is the cell band resource bitmap BITMAP _Cell , and the 16th RB to the 35th RBs of the configured bandwidth are actual. The RB of the transmission bandwidth is a total of 20, and the cell band resource bitmap BITMAP _Cell , RB _Start = 16.

S902, determining whether there is a PBCH in the current subframe to be sent, if yes, executing S903;

S903, marking a bit position of the PBCH corresponding RB as 0, indicating that the corresponding RB has been occupied by the PBCH;

S904. Allocating a frequency band resource for each user, and the method for allocating includes:

a. Maintaining an allocated resource bitmap BITMAP _UE for each user, and recording the RB resources actually occupied by the user, each RB corresponding to one bit position;

b. Starting from RB _Start , determine the bit value corresponding to each RB. If it is 0, assign the RB to the UE, mark the location of the BITMAP _Cell as 2, indicating that it has been allocated; and at the same time, mark the location corresponding to the BITMAP _UE . A value of 1, indicating that the user occupied the RB at this location.

As shown in FIG. 10b, for the allocated cell band resource bitmap BITMAP _Cell , 10 RBs are allocated for the first user, and 10 RB positions of the 16th RB to the 25th RB are marked as 2, as shown in FIG. As shown in FIG. 10c, for the user's frequency resource bitmap BITMAP _UE , a total of 10 RB positions from the 16th RB to the 25th RB are marked as 1.

It should be noted that each of the above modules may be implemented by software or hardware. For the latter, the foregoing may be implemented by, but not limited to, the foregoing modules are all located in the same processor; or, the modules are located in multiple In the processor.

Embodiments of the present invention also provide a storage medium. Optionally, in the embodiment, the foregoing storage medium may be configured to store program code for performing the following steps:

S1. Calculate a first downlink transmission bandwidth of the cell according to the specified cell coverage.

S2. Send downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth.

Optionally, in this embodiment, the foregoing storage medium may include, but not limited to, a USB flash drive, a Read-Only Memory (ROM), a Random Access Memory (RAM), a mobile hard disk, and a magnetic memory. A variety of media that can store program code, such as a disc or a disc.

Optionally, in this embodiment, the processor performs, according to the stored program code in the storage medium, calculating, according to the specified cell coverage, the first downlink transmission bandwidth of the cell.

Optionally, in this embodiment, the processor sends the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth according to the stored program code in the storage medium.

For example, the specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the optional embodiments, and details are not described herein again.

It will be apparent to those skilled in the art that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

According to the embodiment of the present invention, the first downlink transmission bandwidth of the cell is calculated according to the specified cell coverage, and the downlink data of the cell is sent on the frequency resource of the first downlink transmission bandwidth, without changing. On the premise of the cell bandwidth parameter, the cell coverage is increased according to actual needs, and the first downlink transmission bandwidth of the current cell coverage is calculated. By transmitting the downlink data by concentrating the limited power resources to the frequency band resources of the first downlink transmission bandwidth, the transmission power of the unit bandwidth is increased, thereby providing a method for increasing the coverage of the cell, and solving the related art. The problem of increasing RRU cost and inflexible transmission bandwidth caused by increasing cell coverage by reducing the protocol bandwidth supported by the RRU.

Claims

A method for transmitting downlink data of a cell, comprising:

Calculating a first downlink transmission bandwidth of the cell according to the specified cell coverage;

And transmitting downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth.
The method according to claim 1, wherein calculating the first downlink transmission bandwidth of the cell according to the specified cell coverage includes:

Obtaining the specified cell coverage;

Calculating a path loss for transmitting the downlink data on the specified cell coverage;

Calculating the first downlink transmission bandwidth according to the path loss calculation.
The method of claim 2, wherein the calculating the first downlink transmission bandwidth according to the path loss comprises:

Calculating the first downlink transmission bandwidth BW Tx according to the following formula:

The Num p is the number of ports of the cell, and the Num sc is the number of subcarriers on each resource block RB of the downlink data to be sent, where the RRU pwr is the rated transmit power of the cell. ρ A is an offset value of the first type of service symbol relative to the reference signal power, the ρ B is an offset value of the second type of service symbol relative to the reference signal power, and the reference signal power RS pwr =RSRP min + PL, wherein the RSRP min is a cell minimum reception level, and the PL is a path loss for transmitting the downlink data.
The method of claim 1, wherein the transmitting the downlink data of the cell on the frequency domain resource of the first downlink transmission bandwidth comprises:

Determining whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where the minimum bandwidth constraint includes a bandwidth occupied by a physical broadcast channel PBCH;

When the transmission bandwidth is greater than or equal to the minimum bandwidth constraint, downlink data of the cell is sent on a frequency band resource of the first downlink transmission bandwidth.
The method of claim 1, wherein the method further comprises: before transmitting downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth,

Determining whether the downlink data includes both broadcast data and user data;

And when the downlink data includes the broadcast data and the user data, preferentially allocating a first frequency band resource for transmitting the broadcast data from the frequency band resource;

After the first frequency band resource allocation is completed, a second frequency band resource for transmitting the user data is allocated from remaining resources of the frequency band resource.
The method according to any one of claims 1 to 5, wherein the transmitting the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth comprises:

Determining, in the designated resource block RB, the first RB corresponding to the first downlink transmission bandwidth;

And initializing, according to the first RB, a resource bitmap of the frequency band resource, where a bit of the resource bitmap corresponds to the designated RB, and a value of the bit is used to indicate: the bit Whether the corresponding RB is the first RB, whether the first RB is occupied, and a service type that occupies the downlink data of the first RB;

And assigning, according to the resource bitmap and the service type, the first RB to the downlink data, and updating the resource bitmap according to the allocated result;

Transmitting the downlink data of the corresponding service type on the first RB.
A device for transmitting downlink data of a cell, comprising:

a calculating module, configured to calculate a first downlink transmission bandwidth of the cell according to the specified cell coverage;

And a sending module, configured to send downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth.
The apparatus of claim 7 wherein said computing module comprises:

Obtaining a unit, configured to obtain the specified cell coverage;

a first calculating unit, configured to calculate a path loss for transmitting the downlink data on the specified cell coverage;

The second calculating unit is configured to calculate the first downlink transmission bandwidth according to the path loss.
The apparatus of claim 8, wherein the second calculating unit is configured to calculate the first downlink transmission bandwidth BW Tx according to the following formula:

The Num p is the number of ports of the cell, the Num sc is the number of subcarriers on each RB to be sent downlink data, and the RRU pwr is the rated transmit power of the cell, the ρ A is an offset value of the first type of service symbol relative to the reference signal power, the ρ B is an offset value of the second type of service symbol relative to the reference signal power, and the reference signal power RS pwr =RSRP min +PL, The RSRP min is a minimum reception level of the cell, and the PL is a path loss for transmitting the downlink data.
The apparatus of claim 7, wherein the sending module further comprises:

a determining unit, configured to determine whether the first downlink transmission bandwidth is greater than or equal to a minimum bandwidth constraint, where the minimum bandwidth constraint includes a bandwidth occupied by a physical broadcast channel PBCH;

And a determining unit, configured to send downlink data of the cell on a frequency band resource of the first downlink transmission bandwidth when the transmission bandwidth is greater than or equal to a minimum bandwidth constraint.
The apparatus of claim 7 wherein said apparatus further comprises:

a determining module, configured to: before the transmitting module sends the downlink data of the cell on the frequency band resource of the first downlink transmission bandwidth, determining whether the downlink data includes both broadcast data and user data;

a first allocation module, configured to preferentially allocate, from the frequency band resource, a first frequency band resource set to send the broadcast data when the downlink data includes the broadcast data and the user data;

And a second allocation module, configured to allocate a second frequency band resource for transmitting the user data from remaining resources of the frequency band resource after the first frequency band resource allocation is completed.
The device according to any one of claims 7 to 11, wherein the sending module further comprises:

a selected unit, configured to select a first RB corresponding to the first downlink transmission bandwidth in the specified resource block RB;

And an initializing unit, configured to initialize a resource bitmap of the frequency band resource according to the first RB, where a bit of the resource bitmap corresponds to the designated RB, and the value of the bit is used to indicate Whether the RB corresponding to the bit is the first RB, whether the first RB is occupied, and the service type of the downlink data occupying the first RB;

a processing unit, configured to allocate the first RB to the downlink data according to the resource bitmap and the service type, and update the resource bitmap according to the allocated result;

The sending unit is configured to send the downlink data of the corresponding service type on the first RB.