CN110012504A - A kind of information transferring method, base station and network management unit - Google Patents

Abstract

Embodiments of the present invention provide an information transmission method, a base station and a network management unit. The method includes: the base station determines a reference frame structure; the base station determines a first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame The structure at least includes: the frame period of the reference frame and the first reference point. The solution of the present invention effectively avoids the adverse impact of the heterogeneous problem of the base station on the interference management process of the remote base station, and at the same time makes the remote interference fallback more efficient.

Description

An information transmission method, base station and network management unit

technical field

The present invention relates to the field of communications, in particular to an information transmission method, a base station and a network management unit.

Background technique

The remote base station interference phenomenon affects a particularly wide range (hundreds of kilometers), and may involve base stations in multiple cities, provinces, and even multiple countries. Different cities, provinces, and even countries use base station equipment from different manufacturers. If there is no standardized remote interference management mechanism, cooperation between different manufacturers will be particularly difficult.

In view of the above problems, a remote base station interference management mechanism in an LTE network is standardized in the prior art, such as the frame structure shown in Figure 1 and the interference fallback method shown in Figure 2, the remote base station interference management mechanism mainly includes 2 steps:

1) Locate the disturbing base station that causes remote interference;

2) Manually adjust the frame structure of the disturbing base station.

As shown in Figure 1 and Figure 2, the LTE network configures the special subframe (S) as a 9:3:2 structure by default, that is, the special subframe of LTE includes 14 OSs (OFDM symbol, abbreviation for OFDM symbol), among which , OSs #0-#8 are configured as DL, OSs #9-#11 are configured as GP, and the remaining OSs #12-#13 are configured as UL.

1) Locate the disturbing base station that causes remote interference

At least one first base station takes 1024 radio frames as a first period (corresponding to 10.24s), selects a specific radio frame in the first period, and continuously sends a first reference signal, wherein the first reference signal is used for discovering and locating a remote location. end base station interference source.

In particular, the offset of the specific radio frame within the first period is determined by the ID of the first base station. Therefore, when the second base station senses the first reference signal, the partial attributes of the first base station ID can be reversely derived in combination with the offset position of the radio frame where the first reference signal is located within the first cycle.

Specifically, in the selected radio frame, the first base station transmits the first reference signal in the last two OSs (corresponding to OS #7-#8) in the DwPTS of subframe 1 fixed.

On the other hand, the first base station needs to try to detect second reference signals sent by other base stations in all radio frames in the first period, in order to discover and locate remote interference from other base stations.

In particular, the first base station listens to the second base station on 16 OSs in UpPTS and subframe 2 in each radio frame (corresponding to OS numbers #12-#13 of the special subframe, plus all OSs in subframe 2). reference signal.

2) Manually adjust the frame structure of the disturbing base station

Once the first base station detects a certain second reference signal, it reports it to the network management unit.

The network management unit reversely deduces the ID of the third base station according to the offset position of the radio frame where the second reference signal is located in the first period, where the third base station sends the second reference signal.

Subsequently, the special subframe of the third base station is manually reconfigured into a 3:9:2 structure, that is, the #0-#2 OS in the LTE special subframe is configured as DL, and the #3-#11 OS is configured as GP , and the remaining OSs #12-#13 are configured as UL.

Compared with the default 9:3:2 frame structure, the 3:9:2 frame structure uses fewer DL symbols, so it is reasonable to expect that the DL transmission of the base station using the 3:9:2 frame structure can reduce the cost to the base station. UL interference from other remote base stations.

It can be seen from the above introduction that the remote base station interference management method adopted in the LTE existing network has two problems:

1. Not flexible enough: Once the remote interfering base station is located, the interference fallback can only be performed by manually modulating the frame structure;

2. Large performance loss: only the 3:9:2 frame structure can be selected for interference fallback. Compared with 9:3:2, 3:9:2 loses 6 downlink OFDM symbols, and the downlink transmission performance loses more.

In view of the above problem of inflexibility, in the prior art, a remote base station interference management process based on wide-area SON management is proposed, as shown in Figure 3:

1. The base station V detects the interference phenomenon of the remote base station;

2. Report potential interference to the wide area SON;

3. The wide area SON notifies the base station V to send RS1;

4. The wide area SON notifies base station A to listen to RS1;

5. Base station V repeatedly sends RS1;

6. Base station A repeatedly detects RS1;

7. Base station A reports the interference detection result to the wide area SON;

8. The wide area SON configures the interference fallback mechanism for base station A;

9. Base station A performs an interference fallback operation.

In terms of flexibility, compared with the existing technology that uses manual adjustment of frame structure in the existing LTE network, the technology based on wide-area SON base station management shown in Figure 3 can more flexibly coordinate base station behavior and change base station frame structure. Therefore, This method is more flexible.

In terms of fallback performance loss, compared with the prior art in which 6 downlink OFDM symbols are fixed back in the existing LTE network, the technology based on wide-area SON base station management shown in FIG. 3 can be based on the detected interference detection range, Targeted adjustment of DL backoff duration (possibly less than 6 OFDM symbols), so the network performance loss caused by this method is smaller.

In particular, in a homogeneous network (that is, it is assumed that all base stations adopt the same frame structure configuration), the workflow and an example of the management mechanism based on the wide area SON base station are given below.

As shown in FIG. 4 , when a certain TRP is configured to transmit the first RS, the TRP determines to start from the first downlink OFDM symbol (downlink OFDM symbol) before the GP (guard interval) and use at least one downlink OFDM symbol in the forward direction. The RS is transmitted in OFDM symbols. When a certain TRP is configured to receive the first RS, the TRP determines to start from the first uplink OFDM symbol after the GP and use at least one uplink OFDM symbol to listen for the RS in the backward direction. Wherein, the RS can be used to detect the interference phenomenon of the remote base station.

Combined with the remote base station interference management process shown in FIG. 3 and the remote base station interference detection RS time domain transceiver resource locations shown in FIG. 4 , the homogeneous network can work normally.

Figure 5 shows the topology diagram of TRP1 and TRP2;

6 is a schematic diagram of interference characteristics in the data domain, and the UL data of TRP1 and TRP2 are interfered by each other’s DL data;

FIG. 7 is a flowchart of interference management of a remote base station triggered by TRP1 (involving steps 1, 2, 3, 4, 5, 6, and 7). TRP1 sends RS on the last 2 DL OFDM symbols before GP, TRP2 listens for RS on multiple UL OFDM symbols after GP, and reports the listening result: the interference impact interval is 1 OFDM symbol;

Figure 8 is the interference backoff and its effects (involving steps 8, 9). The wide-area SON configures TRP2 to fall back by 2 DL OFDM symbols to eliminate the far-end interference effect of TRP2 on TRP1

As shown in Figure 5 and Figure 6, the distance between TRP1 and TRP2 is about 3.5 OS (OFDM symbol, the abbreviation of OFDM symbol), and they use the exact same frame structure (that is, in the same period, the DL, GP of TRP1 and TRP2 Exactly the same as the UL configuration), and TRP1 and TRP2 are synchronized in time.

Due to the special atmospheric propagation environment, the signals sent by TRP1 and TRP2 on part of the downlink OFDM symbols can reach the other party's part of the uplink OFDM symbols with a certain received power level, and then act as strong interference signals, causing relatively poor UL data transmission performance. strong influence. For example, in FIG. 6 , TRP1 and TRP2 may be interfered by the DL signal from the opposite base station in about 1.5 uplink OFDM symbols after the GP.

TRP1 and TRP2 detect the statistical law of interference signals, determine that the interference may come from the remote base station, and then report it to the wide area SON to trigger the remote base station interference management process based on wide area SON management shown in Figure 3.

Note that TRP1 and TRP2 independently trigger the remote base station interference management process based on wide-area SON management. In FIG. 7 and FIG. 8 , only the related processing after TRP1 triggers the remote base station interference management process based on wide-area SON management, and its effects are illustrated. Through this process, TRP2 performs DL fallback under the configuration of the wide-area SON to eliminate the remote interference caused by it to TRP1.

It can be seen from Fig. 8 that after TRP1 triggers the remote base station interference management process based on wide area SON management, the remote interference caused by TRP2 can be eliminated. However, TRP2 is still subject to distal interference from TRP1. Therefore, a natural operation is that, similar to those shown in FIG. 5 and FIG. 6 , TRP2 also triggers a remote base station interference management process based on wide-area SON management to eliminate the remote interference caused by TRP1. Therefore, after the above operations, TRP1 and TRP2 can effectively eliminate the remote interference caused by them to each other.

In particular, FIG. 7 and FIG. 8 also illustrate the operation details of the remote base station interference management process based on wide-area SON management, including:

Step 1: TRP1 (the base station V in the flowchart, where V represents victim) determines that the interference may come from the remote base station by detecting the statistical law of the interference signal;

Step 2: TRP1 reports the interference situation to the wide area SON to trigger the remote base station interference management process based on the wide area SON management;

Step 3: The wide-area SON notifies TRP1 to send a dedicated remote base station interference sounding reference signal, referred to as the first RS, on the last 2 DL OFDM symbols before the GP;

Step 4: The wide area SON notifies at least one potential interfering base station (base station A in the flowchart, where A represents the aggressor) including TRP2 to listen to the first RS on multiple UL OFDM symbols after the GP;

Step 5: TRP1 sends the first RS according to the wide area SON configuration;

Step 6: TRP2 listens to the first RS according to the wide-area SON configuration, and listens to the first RS in the first uplink OFDM symbol farthest after the GP;

Step 7: TRP2 reports the listening result, including the maximum influence range (such as 1 OFDM symbol), to the wide-area SON;

Step 8: The wide-area SON configures TRP2 to perform an interference back-off operation, so that it backs off at least 2 downlink OFDM symbols;

Step 9: TRP2 performs an interference fallback operation for 2 downlink OFDM symbols according to the wide-area SON configuration, so as to eliminate the far-end interference caused by it to TRP1.

The time-domain resource location of the remote base station interference detection RS shown in Figure 4 can work normally in a homogeneous network (that is, assuming that all base stations use the same frame structure configuration), but in a heterogeneous network (that is, some If the base station adopts different frame structure configuration), it may not work normally and needs to be enhanced.

SUMMARY OF THE INVENTION

The present invention provides an information transmission method, a base station and a network management unit. While effectively avoiding the adverse impact of the heterogeneous problem of the base station on the interference management process of the remote base station, it makes the remote interference fallback more efficient.

In order to solve the above-mentioned technical problems, the embodiments of the present invention provide the following solutions:

An information transmission method, applied to a base station, includes:

the base station determines a reference frame structure;

The base station determines the first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: the frame period of the reference frame and the first reference point.

Wherein, if at least one downlink OFDM symbol is included in the first downlink transmission resource set, at least one of the following methods is adopted for at least one OFDM symbol in the first downlink transmission resource set, including not sending downlink data, limiting the antenna downtilt angle Value range and limit the value range of downlink transmit power.

Wherein, the not sending downlink data further includes:

Adjusting the uplink and/or downlink time domain transmission resource configuration used when the base station communicates with the terminal it serves includes using the downlink OFDM symbol as a guard interval GP or an uplink OFDM symbol.

Wherein, when the base station determines the first downlink transmission resource set, if the distance between the last downlink OFDM symbol and the first reference point is greater than or equal to the first duration, the first downlink transmission resource set is set as an empty set; otherwise, It is set that the first downlink transmission resource set includes at least one continuous downlink OFDM symbol, and it is ensured that the distance between the first OFDM symbol in the first downlink transmission resource set and the first reference point is greater than or equal to the first duration.

Wherein, before the base station determines the first downlink transmission resource set, it further includes:

The base station determines the first duration according to the second duration; or,

The base station receives seventh indication information, and determines the first duration; wherein, the seventh indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling.

Wherein, the reference frame structure further includes: a second reference point.

Wherein, before the base station determines the first duration, it further includes:

The base station determines a second duration; the second duration represents: the time distance from the symbol of the first reference signal that can be sensed farthest after the second reference point to the second reference point.

Wherein, the base station determines the reference frame structure according to at least one method among pre-stipulation, network management unit configuration, and signaling indication between base stations.

Wherein, when the base station determines the reference frame structure through at least one of network management unit configuration and inter-base station signaling indication, it receives at least one of the following indication information:

receiving, by the base station, first indication information, where the first indication information is used to determine the frame period;

The base station receives second indication information, where the second indication information is used to determine a second reference point, wherein the second indication information includes a third duration, and the second reference point is a preset of the frame period The time distance of the boundary is equal to the third duration;

The base station receives third indication information, the third indication information is used to determine the first reference point, wherein the third indication information includes a fourth duration, and the distance between the first reference point and the second reference point is The time distance between them is equal to the fourth duration, and in the frame period, the time corresponding to the first reference point is not earlier than the time corresponding to the second reference point.

Wherein, when the base station determines the reference frame structure through at least one of network management unit configuration and inter-base station signaling indication, it receives at least one of the following indication information:

The base station receives fourth indication information, where the fourth indication information includes: a first transmission transition period and a first upper limit of transmission resources used for downlink transmission in the first transmission transition period;

The base station determines the reference frame structure according to the fourth indication information, including at least one of the following methods:

The base station determines the frame period of the reference frame according to the first transmission transition period;

The base station determines the second reference point according to the first upper limit.

Wherein, the reference frame structure is determined according to at least one of the following methods, including:

The base station determines that the frame period of the reference frame is equal to the first transmission transition period;

The base station determines the maximum available downlink transmission resource set in the first transmission transition period according to the first upper limit; the base station determines that the start time of the second reference point is equal to the last downlink transmission resource in the maximum available downlink transmission resource set end time.

Wherein, the base station starts to monitor the first reference signal from the second reference point.

Wherein, the base station listens to the first reference signal within a fifth time period from the second reference point.

Wherein, the base station determines the fifth duration by pre-determining; or,

The base station receives fifth indication information, and determines a fifth duration; wherein, the fifth indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling.

The base station sends the second reference signal in a time interval [first reference point-sixth duration, first reference point], where the sixth duration is the time domain length of the second reference signal.

Wherein, the base station determines the sixth duration by pre-determining; or,

The base station receives sixth indication information, and determines a sixth duration; wherein, the sixth indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling.

Wherein, the base station listens to the first reference signal in multiple consecutive or non-consecutive reference frames.

Wherein, the base station determines the first duration according to the second duration, and further includes:

first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or,

first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}.

Wherein, the information transmission method further includes:

The base station sends a reporting signaling to the network management unit to report the first measurement result, where the first measurement result is the measurement result of the first reference signal.

Wherein, the reporting signaling also includes at least one of the following information:

the base station identifier, the second duration for at least one first reference signal, the received power of the first reference signal, the received power offset of the first reference signal, and the strength level of the first reference signal;

Wherein, the received power of the first reference signal=the received power offset of the first reference signal+the reference value of the received power offset of the first reference signal.

Wherein, when the reporting signaling includes the received power of the first reference signal, the base station determines the received power of the first reference signal by at least one indication method among pre-regulation, network management unit configuration, and inter-base station signaling. unit;

When the reporting signaling includes the received power offset of the first reference signal, the base station determines the received power offset of the first reference signal by at least one indication method among pre-stipulation, network management unit configuration, and inter-base station signaling. the offset reference value, and the unit of the received power offset of the first reference signal;

When the reporting signaling includes the strength level of the first reference signal, the base station determines the signal strength composed of at least one signal strength level by at least one indication method in pre-regulation, network management unit configuration, and inter-base station signaling. Level collection.

Embodiments of the present invention also provide an information transmission method, applied to a network management unit, including:

Configuring a reference frame structure for at least one first base station and/or a second base station, the reference frame structure includes: a frame period of the reference frame, and at least one of the following information: a second frame period in the frame period of the reference frame Reference point and first reference point.

Among them, the information transmission method also includes:

Receive reporting signaling reported by at least one first base station, where the reporting signaling is used to report a first measurement result; where the first measurement result is a measurement result of the first reference signal.

Wherein, the reporting signaling also includes at least one of the following information:

the base station identifier, the second duration for at least one first reference signal, the received power of the first reference signal, the received power offset of the first reference signal, and the strength level of the first reference signal;

Wherein, the received power of the first reference signal=the received power offset of the first reference signal+the reference value of the received power offset of the first reference signal.

Among them, the information transmission method also includes:

After receiving the reporting signaling from the first base station, the network management unit sends instruction information for performing an interference fallback operation to the base station.

Among them, the information transmission method also includes:

Send network management unit feedback signaling to at least one first base station, where the feedback signaling is used to notify the first duration.

Wherein, before the at least one first base station sends the network management unit feedback signaling, the method further includes:

The network management unit determines the first duration according to the second duration; wherein,

first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or,

first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}.

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

a processor, configured to determine a reference frame structure; and determine a first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: The frame period of the reference frame and the first reference point.

The embodiment of the present invention also provides a network management unit, including:

a processor, configured to configure a reference frame structure for at least one first base station and/or a second base station, where the reference frame structure includes: the frame period of the reference frame, and at least one of the following information: the frame of the reference frame The second reference point and the first reference point in the cycle.

An embodiment of the present invention also provides a communication device, comprising: a processor and a memory storing a computer program, the computer program executing the above method when the processor is run.

Embodiments of the present invention also provide a computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to perform the method as described above.

The above-mentioned scheme of the present invention at least includes the following beneficial effects:

In the above solution of the present invention, by defining a reference frame structure independent of the real frame structure of each base station, each base station transmits/receives remote base station interference detection reference signals according to the reference frame structure, thereby effectively avoiding the heterogeneous problem of base stations. At the same time, it provides a more efficient interference fallback scheme while avoiding the adverse effects caused by the interference management process of the terminal base station.

Description of drawings

1 is a schematic diagram of a frame structure;

Fig. 2 is a schematic diagram of interference fallback;

Fig. 3 is a remote base station interference management process;

Fig. 4 is the time-domain resource position of the transmission and reception of the interference detection RS of the remote base station under the homogeneous network;

Fig. 5 is the topology structure of the base station under the homogeneous network;

FIG. 6 shows that the UL data of TRP1 and TRP2 in the homogeneous network are interfered by each other’s DL data;

7 is a schematic diagram when TRP1 triggers a remote base station interference management process in a homogeneous network;

FIG. 8 is a schematic diagram of the effect of configuring TRP2 to fall back two DLs in a wide-area SON under a homogeneous network;

9 is a schematic diagram of a reference frame structure;

FIG. 10 is a schematic diagram of time-domain resource locations for remote base station interference sounding reference signal transmission/reception;

11 is a schematic diagram of a second duration;

12 is a schematic diagram of an interference fallback mechanism;

FIG. 13 is a schematic diagram of interference fallback in the case of DL alignment, GP lengths are different, and UL misalignment is caused in the heterogeneous network of the present invention;

FIG. 14 is a schematic flowchart of a remote base station interference management technology based on an interference self-suppression working mode;

15 is a schematic diagram of a semi-static frame structure;

FIG. 16 is a schematic diagram of a heterogeneous network.

Detailed ways

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be more thoroughly understood, and will fully convey the scope of the present invention to those skilled in the art.

An embodiment of the present invention provides an information transmission method, applied to a base station, including:

the base station determines a reference frame structure;

The base station determines the first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: the frame period of the reference frame and the first reference point.

In this embodiment of the present invention, the reference frame structure further includes: a second reference point. This embodiment defines a reference frame structure that is independent of the real frame structure of each base station, and each base station sends/receives a reference signal according to the reference frame structure (the reference signal can be used to detect the interference phenomenon of the remote base station), thereby effectively avoiding the different base stations. The adverse impact of the configuration problem on the interference management process of the remote base station.

In a specific embodiment of the present invention, the base station determines the reference frame structure by at least one indication method among pre-specified, network management unit OAM configuration, and inter-base station configuration signaling (backhaul signaling), and the network management unit here can manage multiple base stations.

The pre-stipulation here refers to the pre-determination in the standardized protocol.

The OAM configuration here refers to the static configuration through the network management unit.

Here, the configuration through backhaul signaling between base stations refers to: assuming that there is a global or local network management unit in the network, the network management unit can semi-statically manage and control (including coordination, and/or adjustment) in the network The behavior of some or all base stations. The network management unit may be a physical entity, or just a virtual entity. The network management unit may be called SON, wide area SON, big data processing center, etc. The network management unit configures parameters such as the first period, the second reference point, and the first reference point of the base station through backhaul signaling between base stations.

In a specific embodiment of the present invention, when the base station determines the reference frame structure through at least one indication method in network management unit configuration and inter-base station configuration signaling, it includes at least one of the following information indication information: the base station receives the first indication information, the first indication information is used to determine the frame period;

The base station receives second indication information, where the second indication information is used to determine a second reference point, wherein the second indication information includes a third duration, and the second reference point is a preset of the frame period The time distance of the boundary is equal to the third duration;

The base station receives third indication information, the third indication information is used to determine the first reference point, wherein the third indication information includes a fourth duration, and the distance between the first reference point and the second reference point is The time distance between them is equal to the fourth duration, and in the frame period, the time corresponding to the first reference point is not earlier than the time corresponding to the second reference point.

The preset boundary here may be the end boundary of the frame period, or the start boundary of the frame period, and certainly may be other reference positions in the frame period. When the preset boundary is the right boundary of the reference frame period, the relationship between the third duration and the second reference point and the reference frame structure are shown in FIG. 9 .

In a specific embodiment of the present invention, the base station determines the frame period, the third duration and the fourth duration by at least one indication method among pre-stipulation, network management unit configuration, and configuration signaling between base stations time indicating unit.

Here, the frame period, the third duration and the time indication unit of the fourth duration include: absolute time indication unit (such as seconds, milliseconds, microseconds, etc.) and/or reference OFDM (Orthogonal Frequency Division Multiplexing) symbols number.

Wherein, when the time indication unit is the number of reference OFDM symbols, the base station directly indicates the time length of the reference OFDM symbol, or indirectly indicates the time length of the reference OFDM symbol through at least one kind of indication information among pre-determined, static configuration by the network management unit, and configuration signaling between base stations. The subcarrier spacing SCS of the reference OFDM symbol and the cyclic prefix CP type of the reference OFDM symbol are referenced, and the time length of the reference OFDM symbol is derived.

In another specific embodiment of the present invention, when the base station determines the reference frame structure through at least one of network management unit configuration and inter-base station signaling indication, it receives at least one of the following indication information:

The base station receives fourth indication information, where the fourth indication information includes: a first transmission transition period and a first upper limit of transmission resources used for downlink transmission in the first transmission transition period.

The second transmission transition period configured for the mobile communication terminal by the target cell is the same as the first transmission transition period, and the number of downlink transmission resources in the second transmission transition period is less than or equal to the first upper limit.

The base station determines the reference frame structure according to the fourth indication information, including at least one of the following methods:

The base station determines the frame period of the reference frame according to the first transmission transition period;

The base station determines the second reference point according to the first upper limit.

Wherein, the reference frame structure is determined according to at least one of the following methods, including:

The base station determines that the frame period of the reference frame is equal to the first transmission transition period;

The base station determines the maximum available downlink transmission resource set in the first transmission transition period according to the first upper limit; the base station determines that the start time of the second reference point is equal to the last downlink transmission resource in the maximum available downlink transmission resource set end time.

In a specific embodiment of the present invention, as shown in FIG. 10 , the base station starts to monitor the first reference signal from the second reference point.

In this embodiment, the base station may start listening to the first reference signal from the second reference point and listen to the first reference signal; preferably, the base station determines the fifth duration by pre-specifying; or, the base station receives The fifth indication information is to determine a fifth duration; wherein, the fifth indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling. The fifth duration may adopt any one of the following time indication units, including: absolute time indication units (such as s, ms, us, etc.), and the number of reference OFDM symbols.

In this embodiment, the base station sends the second reference signal within a time interval [first reference point−sixth duration, first reference point], where the sixth duration is the time domain length of the second reference signal.

The base station determines the sixth duration by pre-determining; or, the base station receives the sixth indication information and determines the sixth duration; wherein, the sixth indication information is configured by at least one of the network management unit and the signaling between the base stations. Indicates the method bearer. The sixth duration may adopt any one of the following time indication units, including: absolute time indication units (such as s, ms, us, etc.), and the number of reference OFDM symbols.

In a specific embodiment of the present invention, the base station listens to the first reference signal in a plurality of consecutive or non-consecutive reference frames.

In a specific embodiment of the present invention, the method further includes: the base station determines a second duration; the second duration indicates that the distance between the symbol of the first reference signal and the second reference point can be detected farthest after the second reference point. time distance.

As shown in FIG. 11 , it is a schematic diagram of the second duration. The second duration may adopt any one of the following time indication units, including: absolute time indication units (such as s, ms, us, etc.), and the number of reference OFDM symbols.

After the first base station determines the second duration, the method further includes: the base station determines the first duration according to the second duration; or,

The base station receives seventh indication information, and determines the first duration; wherein, the seventh indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling.

The base station determines the first duration according to the second duration, and further includes:

first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or,

first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}.

In a specific embodiment of the present invention, the information transmission method further includes:

The base station sends a reporting signaling to the network management unit to report the first measurement result, where the first measurement result is the measurement result of the first reference signal.

Specifically, after the first base station obtains the second duration by measuring, the first base station has two processing flow options, including:

Opt 1: The first base station sends the first signaling to the network management unit to report the first measurement result, where the first measurement result is the measurement result of the first reference signal, which corresponds to step 7 in FIG. 3 . After the first base station reports the first measurement result to the network management unit, the first base station waits for the next instruction from the network management unit, that is, the network management unit takes over the subsequent processing flow.

Opt 2: The first base station actively triggers the subsequent processing procedure, including: actively determining the first duration. In the processing flow of Opt 2, the participation of the network management unit is not required. Corresponds to the internal processing of the base station between steps 3 and 4 in FIG. 14 .

The first duration may adopt any one of the following time indication units, including: absolute time indication units (eg, s, ms, us, etc.), and the number of reference OFDM symbols.

In this embodiment, the reporting signaling further includes at least one of the following information: base station identifier, second duration for at least one first reference signal, received power of the first reference signal, and received power of the first reference signal offset and the strength level of the first reference signal; wherein, the received power of the first reference signal = the received power offset of the first reference signal + the reference value of the received power offset of the first reference signal.

Wherein, when the reporting signaling includes the received power of the first reference signal, the base station determines the received power of the first reference signal by at least one indication method among pre-stipulation, OAM (network management unit) configuration, and inter-base station signaling The unit;

When the reporting signaling includes the received power offset of the first reference signal, the base station determines the received power offset reference value of the first reference signal by at least one indication method in pre-determination, OAM configuration, and inter-base station signaling. , and the unit of the received power offset of the first reference signal;

When the reporting signaling includes the strength level of the first reference signal, the base station determines a signal strength level set consisting of at least one signal strength level through at least one indication method among pre-stipulation, OAM configuration, and inter-base station signaling.

In a specific embodiment of the present invention, the method further includes: the base station receives instruction information for performing an interference fallback operation sent to the base station by the network management unit after receiving the reporting signaling of the base station.

In a specific embodiment of the present invention, the method further includes: the base station receives feedback signaling sent by the network management unit, where the feedback signaling (such as the above seventh indication information) is used to notify the first duration.

Specifically, corresponding to step 8 in FIG. 3 , after the network management unit receives the first signaling reported by the first base station, the network management unit will comprehensively consider various factors, such as the measurement results reported by the first base station, to determine whether Let the first base station perform an interference fallback operation.

For example, after at least one third base station that is geographically close to the first base station by the network management unit also reports the first signaling for the first reference signal, and the at least one third base station is performing the interference fallback operation, The network management unit may decide to temporarily not allow the first base station to perform the interference fallback operation.

The network management unit will wait for the interference fallback operation of the at least one third base station to take effect. Since the first base station and the at least one third base station are geographically close, the at least one third base station and the first base station may both be interference sources for the fourth base station (ie, the victim station that transmits the first reference signal). Therefore, after the interference fallback operation of at least one third base station takes effect, the degree of remote interference received by the fourth base station may have been greatly improved, and the reporting of the remote interference discovery event is stopped. At this time, the network management unit will no longer configure the first base station to perform the interference fallback operation.

Otherwise, if the fourth base station still reports the remote interference discovery event after the interference fallback operation of at least one third base station is completed, it means that the interference problem of its remote base station has not been solved. A base station performs interference fallback operations.

In this embodiment, the first duration = the maximum value of the set of durations consisting of the second durations observed for at least one first reference signal; or,

first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}.

Wherein, the first constant=the length of the reference OFDM symbol corresponding to the SCS of the first reference signal.

Further, after the base station determines the first duration, the method further includes: the base station determines a fallback set of downlink OFDM symbols.

Wherein, as shown in FIG. 12, the embodiment of the present invention further includes: when the base station determines the first downlink transmission resource set, wherein:

If the distance between the last downlink OFDM symbol and the first reference point is greater than or equal to the first duration, the first downlink transmission resource set is set to be an empty set; otherwise, the first downlink transmission resource set is set to include at least one continuous The downlink OFDM symbol of the first downlink transmission resource set is guaranteed, and the distance between the first OFDM symbol and the first reference point in the first downlink transmission resource set is guaranteed to be greater than or equal to the first duration.

In a specific embodiment of the present invention, if the first downlink transmission resource set includes at least one downlink OFDM symbol, for at least one OFDM symbol in the first downlink transmission resource set, in order to limit its remote interference strength, the following method is adopted: At least one method includes: not sending downlink data, limiting the value range of the antenna downtilt angle, and limiting the value range of the downlink transmission power; specifically, for each OFDM symbol in the first downlink transmission resource set, in order to limit its The far-end interference strength adopts at least one of the following methods, including: not sending downlink data, limiting the value range of the antenna downtilt angle, and limiting the value range of the downlink transmit power;

The not sending DL data further includes: adjusting the uplink and/or downlink time domain transmission resource configuration used when the base station communicates with the terminal it serves, including using the downlink OFDM symbol as a guard interval GP or an uplink OFDM symbol .

Finally, a specific implementation of the above-mentioned scheme of the present invention is described in conjunction with FIG. 13 and FIG. 14 :

FIG. 14 is a schematic flowchart of the interference management technology of the remote base station based on the interference self-suppression working mode 160, as shown in the figure:

In step 0, the DL data of the interfering station interferes with the UL data receiving behavior of the victim station;

Step 1, the interfered station detects the interference characteristics experienced by the UL data, and determines that it is interfered by the remote base station;

In step 2, the interfered station sends a second reference signal so that it can be detected by other base stations (including the interferer base station). Note that the sending of the second reference signal is conditional, that is, the second reference signal is sent only when the disturbed base station guesses that it is affected by remote interference;

Step 3, the interfering station listens to the second reference signal. Note that the behavior of the interfering station to listen to the second reference signal is unconditional, that is, the interfering station always tries to listen to the second reference signal;

In step 4, after the interfering station detects the second reference signal, the interfering station determines whether to perform an interference fallback operation based on its own independent decision.

As shown in Figure 13 is a heterogeneous network: the case where DL, GP and UL are not aligned:

In the aforementioned comparative solution shown in FIG. 10 , the interference management mechanism of the remote base station will fail. In the solution shown in FIG. 13, however, the interference management mechanism of the remote base station can still work normally.

As shown in Figure 13, the DL alignment of TRP1 and TRP2 has different GP lengths, resulting in UL misalignment; while the UL alignment of TRP1 and TRP3 has different GP lengths, resulting in DL misalignment. TRP1, TRP2 and TRP3 interfere with each other in pairs.

In step 1 of Fig. 13, TRP1 finds that there is remote interference (corresponding to step 1 in the flowchart), and its interference signals come from TRP2 and TRP3.

In step 2 of FIG. 13, TRP1 transmits the remote base station interference detection RS (referred to as the first RS) in the 2 downlink OFDM symbols before the first reference point according to the reference frame structure (corresponding to step 5 in the flowchart); TRP2 and TRP3 listen to the first RS in at least one uplink OFDM symbol after the second reference point according to their own frame structure (corresponding to step 6 in the flowchart). TRP2 and TRP3 sense the first RS farthest in the third uplink OFDM symbol after the second reference point. At this time, TRP2 and TRP3 have two processing flow options, including:

Opt 1: TRP2 and TRP3 send the first signaling to the network management unit to report the first measurement result, where the first measurement result is the measurement result of the first reference signal, corresponding to step 7 in FIG. 3 . Specifically, TRP2 and TRP3 report the listening result (ie, the second duration=3 OFDM symbols) to the wide-area SON. After the first base station reports the first measurement result to the network management unit, the first base station waits for the next instruction from the network management unit, that is, the network management unit takes over the subsequent processing flow.

Correspondingly, the wide-area SON configures TRP2 and TRP3 to perform an interference fallback operation based on the interference measurement results reported by TRP2 and TRP3. The wide area SON determines that the first duration = the second duration + 1 OFDM symbol (the SCS corresponding to the reference frame structure) = 4 OFDM symbols, and configures TRP2 and TRP3 to back off 4 OFDM symbols.

Opt 2: TRP2 and TRP3 actively trigger the subsequent processing flow, including: actively determining the first duration. In the processing flow of Opt 2, the participation of the network management unit is not required, which corresponds to the internal processing of the base station between steps 3 and 4 in FIG. 14 .

Specifically, TRP2 and TRP3 determine that the first duration=the second duration+1 OFDM symbol (the SCS corresponding to the reference frame structure)=4 OFDM symbols.

In step 3 of FIG. 13 , TRP2 and TRP3 determine the actual downlink OFDM symbol backoff set according to the first duration. Specifically, TRP2 determines that the actual downlink OFDM symbol fallback set includes 4 OFDM symbols according to the first duration, which is [#2, #3, #4, #5]; and TRP3 determines the actual downlink OFDM symbols according to the first duration The fallback set includes 2 OFDM symbols, which are [#2, #3].

The final execution effect of step 3 in Figure 13 can be seen. After TRP2 and TRP3 perform interference rollback, they will no longer cause remote interference to TRP1.

However, in the prior art, as shown in FIG. 15 and FIG. 16 , FIG. 15 is a semi-static frame structure configuration that may be adopted by 5G NR, wherein within a preset frame structure period T, the part at the beginning is specified The domain resources are fixed for DL transmission, and some time domain resources at the end are fixed for UL transmission, and the remaining time domain resources in the middle can flexibly determine the data transmission direction, or do not perform any data transmission.

Due to the existence of semi-static frame structure, heterogeneous network should be a typical network feature in 5G NR network.

Figure 16 shows heterogeneous network type 1: DL alignment, GP lengths are different, resulting in UL misalignment; while UL alignment of TRP1 and TRP3, GP lengths are different, resulting in DL misalignment. TRP1, TRP2 and TRP3 interfere with each other in pairs.

In Figure 16-step1, TRP1 finds that there is far-end interference (corresponding to step 1 in the flowchart), and its interference signals come from TRP2 and TRP3.

In Figure 16-step 2, TRP1 sends the remote base station interference detection RS (referred to as the first RS) in the two downlink OFDM symbols before the GP according to its own frame structure (corresponding to step 5 in the flowchart); TRP2 and TRP3 According to its own frame structure, the first RS is sensed in at least one uplink OFDM symbol after the GP (corresponding to step 6 in the flowchart).

TRP3 senses the first RS in the third uplink OFDM symbol after the GP at the farthest, and reports the sensed result to the wide-area SON. However, TRP2 cannot listen to the first RS sent by TRP1, so TRP2 will not report the listening result to the wide-area SON.

In Figure 16-step 3, the wide-area SON configures TRP2 and TRP3 to perform interference fallback operations based on the interference measurement results reported by TRP2 and TRP3. In particular, since the TRP2 does not report the interference measurement result to the wide-area SON, the wide-area SON will not configure the TRP2 to perform an interference fallback operation. However, TRP3 reports to the wide-area SON that it senses the first RS in the third uplink OFDM symbol after the GP, so the wide-area SON will not configure the TRP3 to roll back three downlink OFDM symbols.

However, from the final operation effect of Figure 16-step 3, it can be seen that since TRP2 does not perform the interference fallback operation, its DL signal will still cause remote interference to the UL transmission of TRP1. On the other hand, TRP2 backs off one more downlink OFDM symbol. Although TRP2 will not cause further far-end interference to TRP1 after performing the interference backoff operation, the backoff operation is not the most efficient due to the backoff of some downlink OFDM symbols. Efficient.

In the above-mentioned embodiment of the present invention, as shown in FIG. 13 , after TRP2 and TRP3 perform interference fallback, they will no longer cause remote interference to TRP1.

Embodiments of the present invention also provide an information transmission method, applied to a network management unit, including:

Configuring a reference frame structure for at least one first base station and/or a second base station, the reference frame structure includes: a frame period of the reference frame, and at least one of the following information: a second frame period in the frame period of the reference frame Reference point and first reference point.

Among them, the information transmission method also includes:

Receive reporting signaling reported by at least one first base station, where the reporting signaling is used to report a first measurement result; where the first measurement result is a measurement result of the first reference signal.

Wherein, in the information transmission method, the reporting signaling further includes at least one of the following information:

the base station identifier, the second duration for at least one first reference signal, the received power of the first reference signal, the received power offset of the first reference signal, and the strength level of the first reference signal;

Wherein, the received power of the first reference signal=the received power offset of the first reference signal+the reference value of the received power offset of the first reference signal.

Wherein, the information transmission method further includes:

After receiving the reporting signaling from the first base station, the network management unit sends instruction information for performing an interference fallback operation to the base station.

Wherein, the information transmission method further includes: sending a network management unit feedback signaling to at least one first base station, where the feedback signaling is used to notify the first duration.

Wherein, before the at least one first base station sends the network management unit feedback signaling, the method further includes:

The network management unit determines the first duration according to the second duration; wherein,

first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or,

first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}.

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

a processor, configured to determine a reference frame structure; and determine a first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: The frame period of the reference frame and the first reference point.

It should be noted that the base station may be any base station in the heterogeneous network system, and all the implementations in the methods shown in the above Figures 9 to 13 are applicable to the embodiments of the base station, and the same technical effect can also be achieved .

The embodiment of the present invention also provides a network management unit, including:

a processor, configured to configure a reference frame structure for at least one first base station and/or a second base station, where the reference frame structure includes: the frame period of the reference frame, and at least one of the following information: the frame of the reference frame The second reference point and the first reference point in the cycle.

It should be noted that the network management unit may be a network management unit in a heterogeneous network system, and all the implementation manners in the methods shown in FIG. 9 to FIG. 13 are applicable to the embodiments of the network management unit, and can also achieve The same technical effect.

An embodiment of the present invention also provides a communication device, comprising: a processor and a memory storing a computer program, the computer program executing the above method when the processor is run. Wherein, the processor and the memory are connected through a bus or an interface. The communication device may be a network device, such as a base station, or a network management unit.

Embodiments of the present invention also provide a computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to perform the method as described above.

The above are 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 (31)

1. An information transmission method, applied to a base station, is characterized in that, comprising: the base station determines a reference frame structure; The base station determines the first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: the frame period of the reference frame and the first reference point. 2. information transmission method according to claim 1, is characterized in that, If the first downlink transmission resource set includes at least one downlink OFDM symbol, for at least one OFDM symbol in the first downlink transmission resource set, adopt at least one of the following methods, including not sending downlink data, limiting the value of the antenna downtilt angle range and limit the range of downlink transmit power values. 3. The information transmission method according to claim 2, wherein the not sending downlink data further comprises: Adjusting the uplink and/or downlink time domain transmission resource configuration used when the base station communicates with the terminal it serves includes using the downlink OFDM symbol as a guard interval GP or an uplink OFDM symbol. 4. The information transmission method according to claim 1, wherein when the base station determines the first downlink transmission resource set, if the distance between the last downlink OFDM symbol and the first reference point is greater than or equal to the first duration, Then set the first downlink transmission resource set to be an empty set; otherwise, set the first downlink transmission resource set to include at least one continuous downlink OFDM symbol, and ensure that the first OFDM symbol in the first downlink transmission resource set to the first The distance between a reference point is greater than or equal to the first duration. 5. The information transmission method according to claim 4, wherein before the base station determines the first downlink transmission resource set, the method further comprises: The base station determines the first duration according to the second duration; or, The base station receives seventh indication information, and determines the first duration; wherein, the seventh indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling. 6. The information transmission method according to claim 5, wherein the reference frame structure further comprises: a second reference point. 7. The information transmission method according to claim 6, wherein before the base station determines the first duration, further comprising: The base station determines a second duration; the second duration represents: the time distance from the symbol of the first reference signal that can be sensed farthest after the second reference point to the second reference point. 8 . The information transmission method according to claim 1 or 6 , wherein the base station determines the reference frame structure according to at least one method among pre-stipulation, network management unit configuration, and inter-base station signaling instruction. 9 . 9 . The information transmission method according to claim 8 , wherein, when the base station determines the reference frame structure through at least one of network management unit configuration and inter-base station signaling indication, it receives at least one of the following indications: 10 . information: receiving, by the base station, first indication information, where the first indication information is used to determine the frame period; The base station receives second indication information, where the second indication information is used to determine a second reference point, wherein the second indication information includes a third duration, and the second reference point is a preset of the frame period The time distance of the boundary is equal to the third duration; The base station receives third indication information, the third indication information is used to determine the first reference point, wherein the third indication information includes a fourth duration, and the distance between the first reference point and the second reference point is The time distance between them is equal to the fourth duration, and in the frame period, the time corresponding to the first reference point is not earlier than the time corresponding to the second reference point. 10 . The information transmission method according to claim 8 , wherein, when the base station determines the reference frame structure by at least one of network management unit configuration and inter-base station signaling indication, it receives at least one of the following indications: 11 . information: The base station receives fourth indication information, where the fourth indication information includes: a first transmission transition period and a first upper limit of transmission resources used for downlink transmission in the first transmission transition period; The base station determines the reference frame structure according to the fourth indication information, including at least one of the following methods: The base station determines the frame period of the reference frame according to the first transmission transition period; The base station determines the second reference point according to the first upper limit. 11. The information transmission method according to claim 10, wherein the reference frame structure is determined according to at least one of the following methods, comprising: The base station determines that the frame period of the reference frame is equal to the first transmission transition period; The base station determines the maximum available downlink transmission resource set in the first transmission transition period according to the first upper limit; the base station determines that the start time of the second reference point is equal to the last downlink transmission resource in the maximum available downlink transmission resource set end time. 12. The information transmission method according to claim 7, wherein, The base station starts listening to the first reference signal from the second reference point. 13 . The information transmission method according to claim 12 , wherein the base station listens to the first reference signal within a fifth time period from the second reference point. 14 . 14. The information transmission method according to claim 13, wherein, The base station determines the fifth duration by pre-determining; or, The base station receives fifth indication information, and determines a fifth duration; wherein, the fifth indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling. 15. The information transmission method according to claim 1, wherein the base station sends the second reference signal within a time interval [first reference point-sixth duration, first reference point], wherein the sixth duration is the time domain length of the second reference signal. 16. The information transmission method according to claim 15, wherein, The base station determines the sixth duration by pre-determining; or, The base station receives sixth indication information, and determines a sixth duration; wherein, the sixth indication information is carried by at least one indication method among network management unit configuration and inter-base station signaling. 17. The information transmission method according to claim 12, wherein the base station listens to the first reference signal in a plurality of consecutive or non-consecutive reference frames. 18. The information transmission method according to claim 5, wherein the base station determines the first duration according to the second duration, further comprising: first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or, first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}. 19. The information transmission method according to claim 1, further comprising: The base station sends a reporting signaling to the network management unit to report the first measurement result, where the first measurement result is the measurement result of the first reference signal. 20. The information transmission method according to claim 19, wherein the reporting signaling further comprises at least one of the following information: the base station identifier, the second duration for at least one first reference signal, the received power of the first reference signal, the received power offset of the first reference signal, and the strength level of the first reference signal; Wherein, the received power of the first reference signal=the received power offset of the first reference signal+the reference value of the received power offset of the first reference signal. 21. The information transmission method according to claim 20, wherein, When the reported signaling includes the received power of the first reference signal, the base station determines the unit of the received power of the first reference signal by at least one indication method in pre-regulation, network management unit configuration, and inter-base station signaling; When the reporting signaling includes the received power offset of the first reference signal, the base station determines the received power offset of the first reference signal by at least one indication method among pre-stipulation, network management unit configuration, and inter-base station signaling. the offset reference value, and the unit of the received power offset of the first reference signal; When the reporting signaling includes the strength level of the first reference signal, the base station determines the signal strength composed of at least one signal strength level by at least one indication method in pre-regulation, network management unit configuration, and inter-base station signaling. Level collection. 22. An information transmission method, applied to a network management unit, characterized in that it comprises: Configuring a reference frame structure for at least one first base station and/or a second base station, the reference frame structure includes: a frame period of the reference frame, and at least one of the following information: a second frame period in the frame period of the reference frame Reference point and first reference point. 23. The information transmission method according to claim 22, further comprising: Receive reporting signaling reported by at least one first base station, where the reporting signaling is used to report a first measurement result; where the first measurement result is a measurement result of the first reference signal. 24. The information transmission method according to claim 23, wherein the reporting signaling further comprises at least one of the following information: the base station identifier, the second duration for at least one first reference signal, the received power of the first reference signal, the received power offset of the first reference signal, and the strength level of the first reference signal; Wherein, the received power of the first reference signal=the received power offset of the first reference signal+the reference value of the received power offset of the first reference signal. 25. The information transmission method according to claim 23, characterized in that, further comprising: After receiving the reporting signaling from the first base station, the network management unit sends instruction information for performing an interference fallback operation to the base station. 26. The information transmission method according to claim 23, further comprising: Send network management unit feedback signaling to at least one first base station, where the feedback signaling is used to notify the first duration. 27. The information transmission method according to claim 26, wherein before the at least one first base station sends the network management unit feedback signaling, the method further comprises: The network management unit determines the first duration according to the second duration; wherein, first duration = maximum value of the set of durations consisting of second durations observed for at least one first reference signal; or, first duration = maximum value of a set of durations consisting of at least one {second duration observed for first reference signal + first constant}. 28. A base station, comprising: a processor, configured to determine a reference frame structure; and determine a first downlink transmission resource set according to the distance between the last downlink OFDM symbol and the first reference point in the frame period; wherein, the reference frame structure at least includes: The frame period of the reference frame and the first reference point. 29. A network management unit, characterized in that it comprises: a processor, configured to configure a reference frame structure for at least one first base station and/or a second base station, where the reference frame structure includes: the frame period of the reference frame, and at least one of the following information: the frame of the reference frame The second reference point and the first reference point in the cycle. 30. A communication device, characterized by comprising: a processor and a memory storing a computer program, when the computer program is run by the processor, executes the method according to any one of claims 1-21 or 22- 27 The method of any one. 31. A computer-readable storage medium, characterized in that it comprises instructions that, when the instructions are executed on a computer, cause the computer to perform the method according to any one of claims 1-21 or any one of claims 22-27. method described.