CN111200818B

CN111200818B - Interference avoidance method and device

Info

Publication number: CN111200818B
Application number: CN201811375579.4A
Authority: CN
Inventors: 李志军; 朱雪田; 张志荣
Original assignee: China Telecom Corp Ltd
Current assignee: China Telecom Corp Ltd
Priority date: 2018-11-19
Filing date: 2018-11-19
Publication date: 2022-10-21
Anticipated expiration: 2038-11-19
Also published as: CN111200818A

Abstract

The present disclosure provides an interference avoidance method and apparatus. The interference avoiding device senses the interference degree of the current cell, selects a PCI from a first cell identifier set under the condition that the sensing result is greater than a preset threshold, wherein in the first cell identifier set, REGs corresponding to all PCs are all in an effective bandwidth, and the REGs corresponding to the selected PCI are used for bearing CFI information in a PCFICH channel. According to the method and the device, under the condition that the interference degree of the current cell is greater than the preset threshold, the corresponding PCI is selected to ensure that the REGs bearing the CFI information are all in the effective bandwidth, so that the condition that the CFI information demodulation fails can be effectively avoided.

Description

Interference avoidance method and device

Technical Field

The present disclosure relates to the field of communications, and in particular, to an interference avoidance method and apparatus.

Background

With The development and improvement of 4G (The 4th Generation Mobile Communication Technology, fourth Generation Mobile Communication Technology) and LTE (Long Term Evolution) networks, a large number of users are moving to The LTE network, and network frequency resources are also strained. If the 4G network shares the 2G/3G network frequency band, the wide coverage characteristic of the low frequency band can be utilized to provide higher data transmission rate for users, and the investment cost of 4G on sites and frequency spectrum can be greatly reduced.

Disclosure of Invention

The inventor has noticed that, in order to adapt to different bandwidth frequency spectrums and improve the utilization rate of the scattered frequency spectrum, and simultaneously increase the flexibility of frequency spectrum allocation, LTE supports 6 standard bandwidth operating modes, which are: 1.4M, 3M, 5M, 10M, 15M, 20M, and in practical applications, a suitable bandwidth operating mode may be selected according to the existing frequency band resources.

For example, the chinese telecommunications network C operates in the 800M band, the reverse direction 825M-835M, the forward direction 870M-880M, 7 frequency points including 37, 78, 119, 160, 201, 242, 283, and the newly added frequency point 1019. The frequency points are used for representing nominal frequency point numbers of the network working frequency band and can mark the central frequency of the modulated carrier. In order to make reasonable use of spectrum resources, 1019, 37, 78, 119, 160, 201, 242 of CDMA have 7 frequency points, and a total bandwidth of 8.8M is allocated to LTE. If LTE uses 5M bandwidth mode, 3.8M bandwidth will be wasted, which is not reasonable when spectrum resources are scarce. To overcome this drawback, there is an LTE8.8M non-standard asymmetric scheme in the prior art. However, in this solution, the REG carrying the CFI information in the PCFICH channel may fall outside the effective bandwidth of 8.8M, thereby causing a failure of the terminal to demodulate the CFI information and causing a network-off problem.

Therefore, the present disclosure provides a scheme capable of effectively avoiding the failure of the terminal to demodulate the CFI information due to the REG falling outside the effective bandwidth.

In accordance with an aspect of one or more embodiments of the present disclosure, there is provided an interference avoidance method, including: sensing the interference degree of the current cell; under the condition that the sensing result is larger than a preset threshold, selecting a Physical Cell Identifier (PCI) from a first cell identifier set, wherein in the first cell identifier set, resource particle groups (REG) corresponding to all PCIs are all in an effective bandwidth; the control format indication CFI information in the physical control format indication channel PCFICH is carried with the REG corresponding to the selected PCI.

In some embodiments, in the case that the sensing result is greater than the predetermined threshold, the method further includes: inquiring the PCI used by the adjacent cell; if the PCIs used by the adjacent cells are all from a second cell identifier set, selecting the PCIs from the second cell identifier set, wherein in the second cell identifier set, at least one REG is in an invalid bandwidth in the REGs corresponding to the PCIs; and if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set.

In some embodiments, in the case that the sensing result is not greater than the predetermined threshold, selecting a PCI from the second set of cell identities; then, a step of carrying CFI information in the PCFICH channel using the REG corresponding to the selected PCI is performed.

In some embodiments, in the case that the sensing result is not greater than the predetermined threshold, further comprising: inquiring the PCI used by the adjacent cell; if the PCIs used by the adjacent cells are all from the first cell identification set, selecting the PCIs from the first cell identification set; and if the PCIs used by the adjacent cells are not all from the first cell identification set, selecting the PCIs from the second cell identification set.

In accordance with another aspect of one or more embodiments of the present disclosure, there is provided an interference avoidance apparatus including: the sensing module is configured to sense the interference degree of the current cell; a selecting module configured to select a physical cell identifier PCI from a first cell identifier set when a sensing result is greater than a predetermined threshold, where in the first cell identifier set, resource particle groups REG corresponding to PCIs are all within an effective bandwidth; a bearer module configured to carry the control format indication CFI information in the physical control format indication channel PCFICH with the REG corresponding to the selected PCI.

In some embodiments, the selecting module is configured to query PCIs used by the neighboring cell if the sensing result is greater than a predetermined threshold, and select a PCI from a second cell identity set if the PCIs used by the neighboring cell are all from the second cell identity set, where in the second cell identity set, at least one REG in REGs corresponding to PCIs is within an invalid bandwidth; and if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set.

In some embodiments, the selecting module is further configured to select a PCI from the second set of cell identities if the sensing result is not greater than the predetermined threshold, and then instruct the bearer module to perform an operation of carrying the CFI information in the PCFICH channel using the REG corresponding to the selected PCI.

In some embodiments, the selection module is further configured to query the PCIs used by the neighboring cells if the sensing result is not greater than the predetermined threshold, select the PCIs from the first cell identification set if the PCIs used by the neighboring cells are all from the first cell identification set, and select the PCIs from the second cell identification set if the PCIs used by the neighboring cells are not all from the first cell identification set.

In accordance with another aspect of one or more embodiments of the present disclosure, there is provided an interference avoidance apparatus including: a memory configured to store instructions; a processor coupled to the memory, the processor configured to perform a method according to any of the embodiments described above based on instructions stored in the memory.

According to another aspect of one or more embodiments of the present disclosure, a computer-readable storage medium is provided, in which computer instructions are stored, and when executed by a processor, the computer instructions implement the method according to any one of the embodiments described above.

Other features of the present disclosure and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and for those skilled in the art, other drawings may be obtained according to the drawings without inventive labor.

Fig. 1 is a schematic diagram of frequency point occupation of an LTE8.8M non-standard asymmetric scheme according to the present disclosure;

fig. 2 is a schematic diagram of a basic processing flow of the disclosed PCFICH physical channel;

fig. 3 is an exemplary flow chart of an interference avoidance method of one embodiment of the present disclosure;

fig. 4 is an exemplary flow chart of an interference avoidance method of another embodiment of the present disclosure;

FIG. 5 is an exemplary block diagram of a disturbance avoidance apparatus of one embodiment of the present disclosure;

fig. 6 is an exemplary block diagram of an interference avoidance apparatus of another embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be described clearly and completely with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the embodiments described are only some embodiments of the present disclosure, rather than all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without inventive step, are intended to be within the scope of the present disclosure.

The relative arrangement of parts and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Fig. 1 is a schematic diagram of frequency point occupation in an LTE8.8M non-standard asymmetric scheme. As shown in fig. 1, the LTE network employs a 10M bandwidth mode, as shown by a in fig. 1. At this time, seven

frequency points

1019, 37, 78, 119, 160, 201, and 242 are occupied by LTE, that is, the effective bandwidth is 8.8M, as shown in b in fig. 1.

The PCFICH (Physical Control Format Indication Channel) belongs to an LTE Physical layer downlink Control Channel, and is mainly responsible for transmitting a CFI (Control Format Indication) to indicate the number of OFDM (Orthogonal Frequency Division Multiplexing) symbols occupied by the Physical Control Channel in each subframe.

Fig. 2 is a schematic diagram of a basic processing flow of the disclosed PCFICH physical channel. As shown in fig. 2, the CFI information is encoded, scrambled and modulated to form 16 modulation symbol information, and the information is divided into 4 segments, where each segment corresponds to one OFDM Resource Element Group REG (Resource Element Group). One REG includes 4 consecutive Resource elements RE (Resource elements).

The subcarrier position of the REG corresponding to each information segment is obtained by the following formula:

z ^(p) (0) The corresponding REG location formula is:

wherein

Z ^(p) (1) The corresponding REG location formula:

z ^(p) (2) The corresponding REG location formula:

z ^(p) (3) The corresponding REG location formula:

wherein p is the antenna port,

indicates the number of RBs (Resource blocks) under the bandwidth,

indicates the number of sub-carriers in one RB,

denotes a Physical Cell identity PCI (Physical Cell Identifier).

In the LTE8.8M non-standard scenario, although LTE adopts a 10M bandwidth mode, the actual effective bandwidth is only 8.8M, and the other 1.2M bandwidth will be compressed. However, the PCFICH channels are still uniformly distributed according to the 10M bandwidth, that is, part of the CFI information may be allocated outside the 8.8M bandwidth, which may cause the terminal to be unable to detect the CFI information outside the 8.8M bandwidth, thereby causing a network drop situation caused by failure in demodulating the CFI information.

For example, the CFI information in the PCFICH channel is segmented into four segments and carried with REG0, REG1, REG2, REG3, respectively. Under the LTE8.8M nonstandard asymmetric scheme scene, each REG carrying CFI information has a certain probability of falling outside the 8.8M effective bandwidth.

Fig. 3 is an exemplary flowchart of an interference avoidance method according to an embodiment of the present disclosure. In some embodiments, the method steps of the present embodiment may be performed by an interference avoidance device.

In step 301, the interference level of the current cell is sensed.

In step 302, a PCI is selected from the first set of cell identities in case the sensing result is larger than a predetermined threshold. In the first cell identifier set, the resource element groups REG corresponding to each PCI are all within the effective bandwidth.

In the first cell identifier set, the resource particle groups REG corresponding to each PCI are all within the effective bandwidth, so that the condition that the REGs fall outside the effective bandwidth can be avoided.

In step 303, the CFI information in the PCFICH channel is carried with the REG corresponding to the selected PCI.

In the interference avoidance method provided by the above embodiment of the present disclosure, when the interference degree of the current cell is greater than the predetermined threshold, the corresponding PCI is selected to ensure that the REGs carrying the CFI information are all within the effective bandwidth. Therefore, the condition that the CFI information is demodulated and failed can be effectively avoided.

In some embodiments, in the case that the sensing result is greater than the predetermined threshold, the PCIs used by the neighboring cells are further queried, and if the PCIs used by the neighboring cells are all from a second cell identity set, the PCIs are selected from the second cell identity set, where in the second cell identity set, at least one REG in REGs corresponding to the PCIs is within an invalid bandwidth. And if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set.

That is, if the interference of the current cell is large and at least some of the neighboring cells use the PCI from the first cell identity set, in this case, the PCI is selected from the first cell identity set. If the current cell has large interference, the adjacent cells use the PCI from the second cell identification set. In this case, the PCI is then selected from the second set of cell identities. Therefore, the problem of interference in switching can be avoided, and the switching success rate is effectively improved.

In the case where the CFI information in the PCFICH channel is carried by REG0, REG1, REG2, and REG3, table 1 gives the location where the first RE of REG0 to REG3 is located under different PCIs. The dark regions in table 1 represent REGs that fall outside the effective bandwidth and the corresponding PCI values.

TABLE 1

According to table 1, the PCI used by the cell in different scenarios can be planned and allocated.

Cells are divided into two groups according to PCI value: the cells (PCI increased by 100 cycles) having PCIs {15, \8230;, 35,40, \8230;, 60,65, \8230;, 85,90, \8230;, 99}, {115, \8230;, 135,140, \8230;, 160,165, \8230;, 185,190, \8230;, 199} etc. are the second set. And setting the cells with the PCIs with other values as a first set.

For areas with large interference, such as dense urban areas, the first set of PCIs is used as much as possible to avoid the REGs carrying CFI information falling outside the effective bandwidth. And for areas where the interference is relatively small or insensitive, such as rural areas, it may be desirable to use the second set of PCIs to conserve the first set of PCI resources.

Fig. 4 is an exemplary flowchart of an interference avoidance method according to another embodiment of the present disclosure. In some embodiments, the method steps of the present embodiment may be performed by an interference avoidance device.

In step 401, the interference level of the current cell is sensed.

In step 402, a PCI is selected from the second set of cell identities in case the sensing result is not larger than a predetermined threshold.

In step 403, the CFI information in the PCFICH channel is carried with the REG corresponding to the selected PCI.

For example, for areas with less interference, such as rural areas, the second set of PCIs is used in order to save the first set of PCI resources.

In some embodiments, in case the sensing result is not greater than the predetermined threshold, the PCI used by the neighboring cell is further queried. And if the PCIs used by the adjacent cells are all from the first cell identification set, selecting the PCIs from the first cell identification set. And if the PCIs used by the adjacent cells are not all from the first cell identification set, selecting the PCIs from the second cell identification set.

That is, if the interference of the current cell is small and at least some of the neighboring cells use the PCI from the second cell identity set, in this case, the PCI is selected from the second cell identity set to meet the requirement. If the interference of the current cell is small, the adjacent cells use the PCI from the first cell identification set. In this case, the PCI is then selected from the first set of cell identities. Therefore, the problem of interference in switching can be avoided, and the switching success rate is effectively improved.

Fig. 5 is an exemplary block diagram of an interference avoidance apparatus according to an embodiment of the present disclosure. As shown in fig. 5, the interference avoidance apparatus includes a sensing module 51, a selecting module 52, and a carrying module 53.

The sensing module 51 is configured to sense the interference level of the current cell.

The selecting module 52 is configured to select a PCI from a first cell identifier set in which the resource element group REG corresponding to each PCI is within the effective bandwidth, if the sensing result is greater than a predetermined threshold.

The bearer module 53 is configured to carry the control format indication CFI information in the PCFICH channel with the REG corresponding to the selected PCI.

In the interference avoidance provided by the above embodiment of the present disclosure, when the interference degree of the current cell is greater than the predetermined threshold, the corresponding PCI is selected to ensure that the REGs carrying the CFI information are all within the effective bandwidth. Therefore, the condition that the CFI information is demodulated and failed can be effectively avoided.

In some embodiments, the selecting module 52 is configured to query the PCIs used by the neighboring cells if the sensing result is greater than the predetermined threshold, and select the PCI from the second cell identification set if the PCIs used by the neighboring cells are all from the second cell identification set. In the second cell identifier set, at least one REG in the REGs corresponding to each PCI is within the invalid bandwidth. And if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set.

That is, if the interference of the current cell is large and there is a cell in the neighboring cells that uses the PCI from the first cell identity set, in this case, the PCI is selected from the first cell identity set. If the interference of the current cell is larger, the adjacent cells use the PCI from the second cell identification set. In this case, the PCI is then selected from the second set of cell identities. Therefore, the problem of interference in switching can be avoided, and the switching success rate is effectively improved.

In some embodiments, the selecting module 52 is further configured to select a PCI from the second set of cell identities if the sensing result is not greater than the predetermined threshold, and then instruct the carrying module 53 to perform an operation of carrying the CFI information in the PCFICH channel with the REG corresponding to the selected PCI.

In some embodiments, the selecting module 52 is further configured to query the PCIs used by the neighboring cells if the sensing result is not greater than the predetermined threshold, select the PCIs from the first cell identification set if the PCIs used by the neighboring cells are all from the first cell identification set, and select the PCIs from the second cell identification set if the PCIs used by the neighboring cells are not all from the first cell identification set.

That is, if the interference of the current cell is small and there is a cell in the neighboring cell that uses the PCI from the second cell identity set, in this case, it is sufficient to select the PCI from the second cell identity set. If the interference of the current cell is small, the adjacent cells use the PCI from the first cell identification set. In this case, the PCI is then selected from the first set of cell identities. Therefore, the problem of interference in switching can be avoided, and the switching success rate is effectively improved.

Fig. 6 is an exemplary block diagram of a disturbance avoidance apparatus of yet another embodiment of the present disclosure. As shown in fig. 6, the interference avoidance apparatus includes a memory 61 and a processor 62.

The memory 61 is used for storing instructions, the processor 62 is coupled to the memory 61, and the processor 62 is configured to execute the method according to any one of the embodiments in fig. 3 or fig. 4 based on the instructions stored in the memory.

As shown in fig. 6, the interference avoidance apparatus further includes a communication interface 63 for information interaction with other devices. Meanwhile, the device also comprises a bus 64, and the processor 62, the communication interface 63 and the memory 61 are communicated with each other through the bus 64.

The memory 61 may comprise high-speed RAM memory, and may also include non-volatile memory (non-volatile memory), such as at least one disk memory. The memory 61 may also be a memory array. The storage 61 may also be partitioned and the blocks may be combined into virtual volumes according to certain rules.

Further, the processor 62 may be a central processing unit CPU, or may be an application specific integrated circuit ASIC, or one or more integrated circuits configured to implement embodiments of the present disclosure.

The present disclosure also relates to a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the instructions, when executed by a processor, implement a method according to any one of the embodiments shown in fig. 3 or fig. 4.

In some embodiments, the functional unit modules described above can be implemented as a general purpose Processor, a Programmable Logic Controller (PLC), a Digital Signal Processor (Digital Signal Processor, DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable Logic device, discrete Gate or transistor Logic, discrete hardware components, or any suitable combination thereof for performing the functions described in this disclosure.

By implementing the present disclosure, the following advantageous effects can be obtained:

1) Under the condition of asymmetric effective bandwidth, only the PCI planning area and range need to be adjusted, and the internal algorithm of the base station does not need to be changed;

2) Interference is avoided under an 8.8M nonstandard asymmetric scene by newly grouping and pairing PCI, and the demodulation success rate is improved;

3) And the success rate of switching among cells is improved.

When the 3G network of the operator gradually reduces the frequency and only reserves one 2G frequency point (only 1X frequency point is reserved for inert users and military network users), the stage is a long-term existing state and can be applied to hundreds of thousands of conventional 800M 4G base stations of the operator.

The advantages of the present disclosure are also embodied in:

1) Only the algorithm needs to be enhanced, hardware does not need to be changed, and engineering construction is not needed;

2) The 4G heavy plowing investment of the current 800M network of the China telecom is hundreds of billions of yuan, and if the technology is applied to the current network, the capacity expansion investment of the 800M network of the China telecom can be greatly saved.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing relevant hardware, where the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

The description of the present disclosure has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to practitioners skilled in this art. The embodiment was chosen and described in order to best explain the principles of the disclosure and the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.

Claims

1. An interference avoidance method, comprising:

sensing the interference degree of the current cell;

under the condition that the sensing result is larger than a preset threshold, selecting a Physical Cell Identifier (PCI) from a first cell identifier set, wherein in the first cell identifier set, resource particle groups (REG) corresponding to all PCIs are all in an effective bandwidth;

bearing Control Format Indication (CFI) information in a Physical Control Format Indication Channel (PCFICH) by using the REG corresponding to the selected PCI;

wherein, under the condition that the sensing result is greater than the predetermined threshold, the method further comprises the following steps:

inquiring the PCI used by the adjacent cell;

if the PCIs used by the adjacent cells are all from a second cell identifier set, selecting the PCIs from the second cell identifier set, wherein in the second cell identifier set, at least one REG in the REGs corresponding to the PCIs is in an invalid bandwidth;

and if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set.

2. The method of claim 1, further comprising:

selecting a PCI from the second cell identification set under the condition that the sensing result is not greater than a preset threshold;

then, a step of carrying CFI information in the PCFICH channel using the REG corresponding to the selected PCI is performed.

3. The method of claim 2, wherein in case the perception result is not greater than the predetermined threshold, further comprising:

inquiring the PCI used by the adjacent cell;

if the PCIs used by the adjacent cells are all from the first cell identification set, selecting the PCIs from the first cell identification set;

and if the PCIs used by the adjacent cells are not all from the first cell identification set, selecting the PCIs from the second cell identification set.

4. An interference avoidance apparatus comprising:

the sensing module is configured to sense the interference degree of the current cell;

a selecting module configured to select a physical cell identifier PCI from a first cell identifier set when a sensing result is greater than a predetermined threshold, where in the first cell identifier set, resource particle groups REG corresponding to each PCI are all within an effective bandwidth, where in the sensing result is greater than the predetermined threshold, a PCI used by an adjacent cell is queried, and if the PCIs used by the adjacent cell are all from a second cell identifier set, a PCI is selected from a second cell identifier set, where in the second cell identifier set, at least one REG in the REGs corresponding to each PCI is within an invalid bandwidth; if the PCIs used by the adjacent cells are not all from the second cell identification set, selecting the PCIs from the first cell identification set;

a bearer module configured to carry the control format indication CFI information in the physical control format indication channel PCFICH with the REG corresponding to the selected PCI.

5. The apparatus of claim 4, wherein,

the selecting module is further configured to select a PCI from the second set of cell identities if the sensing result is not greater than the predetermined threshold, and then instruct the carrying module to perform an operation of carrying the CFI information in the PCFICH channel using the REG corresponding to the selected PCI.

6. The apparatus of claim 5, wherein,

the selection module is further configured to query PCIs used by the neighboring cells when the sensing result is not greater than the predetermined threshold, select a PCI from the first cell identifier set if the PCIs used by the neighboring cells are all from the first cell identifier set, and select a PCI from the second cell identifier set if the PCIs used by the neighboring cells are not all from the first cell identifier set.

7. An interference avoidance apparatus comprising:

a memory configured to store instructions;

a processor coupled to the memory, the processor configured to perform implementing the method of any of claims 1-3 based on instructions stored by the memory.

8. A computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions which, when executed by a processor, implement the method of any one of claims 1-3.