TWI433559B - A method and a mobile station for providing an interference measurement result, a method for configuring radio resource allocation ,a method for scheduling a mobile station, and a cellular orthogonal frequency division multiple access system - Google Patents

Description

Method and mobile station for providing interference measurement results, method for configuring radio resources, method for data transmission scheduling, and honeycomb orthogonal frequency division multiple access system

The present invention relates to a Orthogonal Frequency Division Multiple Access (OFDMA) system, and in particular to an interference measurement mechanism for adaptive frequency reuse.

In wireless mobile systems, frequency reuse is an important technology that increases the capacity of the entire system by reusing rare radio spectrum resources. However, the increase in system capacity is accompanied by an increase in the intensity of the interference, which may result in deterioration of the connection quality. In the cellular OFDMA system, since the signals of different users are maintained orthogonal during transmission, there is no intra-cell interference. However, since the same frequency band is also reused by the base station of the neighboring unit, repeated use of the radio spectrum (i.e., frequency reuse) will cause inter-cell interference.

FIG. 1 is a schematic diagram of a unit architecture of a cellular OFDMA system 1 of the prior art. The cellular OFDMA system 1 includes a unit structure in which the frequency reuse factor 1/K is equal to 1/4. The frequency reuse factor 1/K represents the number of cells that cannot share the same frequency band when transmitting. In the example shown in Figure 1, the entire licensed spectrum is divided into four bands, and every four adjacent units make up a cluster, so each unit in the cluster can be served by a different frequency band. In one example, the base station BS4 shares the same frequency band #1 with the base station BS5, serving the mobile station MS6 located in the unit 2 and the mobile station MS7 located in the unit 3, respectively. As a result, when BS4 transmits a data signal to communicate with MS6, BS5 also transmits a data signal to MS7 at the same time. Since the signal transmitted by BS4 to MS6 is not the signal that MS7 expects to receive but is transmitted in the same frequency band. Therefore, this signal will cause interference to MS7. This interference signal reduces the signal to interference-plus-noise ratio (SINR) of the mobile station MS7, thus reducing the overall quality of service. This problem can be improved by setting a smaller frequency reuse factor of 1/K to extend the distance between the interferer and the receiver (for example, sqrt(3K)*R, where R is the cell radius), but each The radio resources available in one unit are thus degraded (for example, 1/K licensed spectrum) resulting in a reduction in system capacity.

Compared with the traditional frequency reuse method, Fractional Frequency Reuse (FFR) has been proposed for the cellular OFDMA system to achieve a better tradeoff between system capacity and service quality. 2A and 2B are schematic diagrams showing the FFR used in the cellular OFDMA system 10 for the display of the prior art. The cellular OFDMA system 10 includes a unit 11, and the unit 11 is divided into a first area and a second area. The first zone is located closer to the geographic location of the service base station BS12, while the second zone is located closer to the geographic base station BS12. In addition, the radio spectrum of the cellular OFDMA system 10 is divided into a frame zone #1 and a frame zone #2 in the time domain. Under the adaptive frequency reuse technique, different frame zones and different frequency reuse factors are applied to serve mobile stations located in different zones. In the examples of FIG. 2A and FIG. 2B, the first frame area uses a higher frequency reuse factor (ie, 1/K is equal to 1) to serve the first area, and the second frame area is used. A low frequency reuse factor (ie: 1/K equals 1/3) to service the second zone. Therefore, the mobile station MS17 located in the first area is served by the base station BS12 using the first frame area having the frequency reuse factor 1/K equal to 1 (e.g., 9A), and the mobile station MS18 located in the second area is served by the base station BS12. Serve (eg, 9B) using a second frame area with a frequency reuse factor of 1/K equal to 1/3. Since the mobile station MS17 is located closer to the center of the unit 11, it can be assumed that it receives a stronger data signal from the BS 12 and a relatively weaker interference signal from a neighboring interference source. On the other hand, since the mobile station MS 18 is located closer to the boundary of the unit 11, it can be assumed that it receives a relatively weak data signal from the BS 12 and a relatively strong interference signal from a neighboring interference source. Therefore, by using a higher repetition factor (1/K) to serve MS1 and a lower repetition factor (1/K) to serve MS2, a good balance between system capacity and service quality can be achieved.

Unfortunately, location-based FFR technology is not always effective. As shown in FIGS. 2A and 2B, a physical structure 14 is blocked between the mobile station MS 18 and the interfering base station BS 13. Therefore, the interfering base station BS13 transmits a relatively strong interference signal 15 to the MS 17 and transmits a relatively weak interference signal 16 to the MS 18. As described above, in the case where there is a frequency reuse mode based on the cell region, the MS 17 located in the first region is subjected to strong interference from the BS 13 but uses a higher 1/K equal to 1, and the MS 18 located in the second region enjoys The better service quality is lower than 1/K equal to 1/3. Therefore, location-based FFR technology is not suitable for dynamic network conditions. In a radio communication system, dynamic measurement interference must be performed to maintain a good balance between connection quality and system capacity, and the frequency reuse mode and radio resource allocation are determined according to the results of the interference measurement. Big challenge.

The interference measurement mechanism has been applied to conventional wireless communication systems. For example, a traditional cellular split multiple access (such as GSM) or a code division multiple access system transmits and receives narrow band signals by the transceiver. Because of the narrowband nature, the crossover multiple access system can only measure signal power or interference over a single time-frequency region in a given time. The frequency division multiplexing system is not free to measure in different time-frequency regions because the RF center frequency of the frequency division multiplexing system must be adjusted accordingly to be able to measure. In contrast, in the orthogonal frequency division multiple access system, a wideband signal is transmitted and received by a transceiver having a Fast Fourier Transfer function. Such an OFDMA system can easily transmit and receive signals to any given time-frequency region over a wide channel bandwidth. Therefore, the transceiver of the OFDMA system can freely measure signal power or interference in a time-frequency region different from the time-frequency region of the received data without changing the radio frequency center frequency. This is the biggest difference between the OFDMA system and other traditional cellular multi-frequency multi-access multi-access systems or code-multiple access systems.

In order to solve the above technical problems, the present invention provides a method and a mobile station for providing interference measurement results, a method for configuring radio resources, a data transmission scheduling method, and a cellular orthogonal frequency division multiple connection Take the system.

The present invention provides a method for providing interference measurement results using at least one mobile station to assist an OFDMA system to support frequency division multiplexing, the method comprising: using the at least one mobile station to measure on a time-frequency region Measuring interference statistics to obtain interference measurement results in the cellular orthogonal frequency division multiple access system, wherein the mobile station is located in a unit served by the service base station; and reporting the interference measurement result to the Service base station.

The present invention provides a mobile station for providing interference measurement results, and an auxiliary honeycomb orthogonal frequency division multiple access system for enabling frequency multiplexing, the mobile station comprising: a measurement module, wherein the measurement module is The interference statistic is measured in the cellular orthogonal frequency division multiple access system, and the interference measurement result is obtained according to the data, wherein the mobile station reports the interference measurement result to the network unit.

The invention provides a mobile station, comprising: a transceiver; and a measuring device, wherein the measuring device measures the interference statistic in the honeycomb orthogonal frequency division multiple access system, and obtains the interference measurement result according to the method, wherein The measuring device reports the interference measurement result to the network unit of the cellular orthogonal frequency division multiple access system.

The present invention provides a method for configuring a radio resource, comprising: obtaining a plurality of interference measurement results of a mobile station located in a unit of a cellular orthogonal frequency division multiple access system; and obtaining a plurality of interference measurement results according to at least a portion Determine the frequency reuse mode and configure the corresponding radio resource allocation.

The present invention provides a cellular orthogonal frequency division multiple access system, comprising: a plurality of mobile stations, measuring a plurality of interference statistics and obtaining a plurality of interference statistic results therefrom; and a network unit receiving the plurality of The interference measurement result, wherein the network unit determines the multiple frequency division multiplexing mode and the corresponding radio resource allocation according to the at least a part of the received interference measurement results.

The present invention provides a method for data transmission scheduling, comprising: obtaining an interference measurement result by a base station in a cellular orthogonal frequency division multiple access system; and arranging according to at least a part of the obtained interference measurement result The Chengyi Mobile Station is served by a radio resource area.

The present invention provides a cellular orthogonal frequency division multiple access system, comprising: a mobile station; and a service base station, obtaining interference measurement results, and scheduling the mobile station based on at least a part of the interference measurement result To serve by a radio resource area.

The method and the mobile station for providing interference measurement results, the method for configuring radio resources, the method for data transmission scheduling, and the cellular OFDMA system provided by the present invention are suitable for adaptive frequency reuse technology The frequency reuse pattern is in different radio resource regions, thereby reducing interference between units and increasing system capacity. In addition, adaptive frequency reuse further coordinates radio resource allocation scheduling, power allocation, antenna configuration, and channelized formats to optimize system performance.

3A and 3B are diagrams showing a cellular OFDMA system 20 in accordance with an embodiment of the present invention, wherein 19A, 19B are mobile station action content; 19C is base station action content. The cellular OFDMA system 20 includes a unit 21, a serving base station BS22, and a plurality of mobile stations MS23, MS24, MS25 located in the unit 21. Each mobile station includes a transceiver 26, a measurement module 27, an analog baseband circuit 28, a digital baseband circuit 29, and a memory 30. The cellular OFDMA system 20 uses adaptive frequency reuse (also known as FFR) techniques to reduce inter-cell interference. In the examples of Figures 3A and 3B, all available frequency channels within the cellular OFDMA system 20 are sliced into three different radio resource regions #1, #2, and #3. The radio resource region is cut in the time domain, or in the frequency domain, or a combination of the time domain and the frequency domain. Each radio frequency region employs a corresponding frequency reuse factor to service the mobile stations located within unit 21. According to a first aspect of the invention, each of the mobile stations located within unit 21 is served by an appropriate frequency reuse factor based on the interference measurement results obtained by itself. As shown in Figures 3A and 3B, for downlink FFR control, each mobile station first measures its interference statistic over a given time-frequency region and obtains interference measurements ( Such as 19A). The interference measurement statistic may be interference power, signal to interference ratio (SIR), signal to interference-plus-noise ratio (SINR), or some other Interfere with information to indicate. Interference measurement results can be obtained directly from interference statistics or indirectly from interference statistics. For example, the interference measurement statistic result may be represented by interference power, SIR, SINR, index indication, and preferred and non-preferred radio resource area indicators or other SIRs. /SINR derived form to represent. Each mobile station then reports the interference measurement results to the serving base station BS22 (e.g., 19B). Based on the received interference measurement results, the service station BS22 schedules each mobile station to serve (e.g., 19C) by the corresponding radio resource area and the appropriate radio resource area, thereby optimizing the performance of the connection. And maximize system capacity.

Figure 4 is a flow chart of the measurement of interference statistics and reported interference statistics for a cellular OFDMA system. There are different interference measurement mechanisms. Among the requested interference measurement mechanisms, the mobile station first issues a request for interference measurement to the base station in service (step 31). After the request, the mobile station receives an indication of the interference measurement from the serving base station (step 32). In step 34, the mobile station measures its interference statistics for a given time-frequency region and then obtains the interference measurement results. The given time-frequency region is provided by the interference measurement indication. In the final step 35, the mobile station reports the interference measurement results to the serving base station. In the unsolicited interference measurement mechanism, the mobile station does not transmit the interference measurement request. Instead, the service base station directly instructs the mobile station to perform interference measurements. The mobile station then performs the same steps 34 and 35 to measure the interference statistics and report the interference statistics results to the serving base station. In the autonomous interference measurement mechanism, there is no interference measurement request, and there is no interference measurement indication that the mobile station communicates with the base station. Instead, the mobile station receives the resource allocation message broadcast by the serving base station (step 33). By decoding the resource allocation message, the mobile station obtains a given time-frequency region that can be used for interference measurement. The mobile station then measures its interference statistics according to the same steps 34 and 35, and reports the interference measurement results to the serving base station.

5A and 5B show the requested interference measurement mechanism and the unsolicited interference measurement mechanism used in the unit 40 of the cellular OFDMA system, where 39A is the action content of the mobile station; 39B is the action content of the base station ; 39C is the given time-frequency region. The mobile stations MS42, MS43, and MS44 are located in the unit 40 and are served by the base station BS41. In Figure 5B, the downlink frame of unit 40 is divided into N different frame regions (frame regions #1-#N) in the time domain. Under the requested interference measurement mechanism, the mobile stations MS42, MS43 and MS44 first request the serving base station BS41 to instruct the mobile station to measure their interference statistics (e.g., 39A). Upon receiving the request, the service base station instructs each mobile station to perform interference measurements (such as 39B) on a given time-frequency region (such as 39C) in each frame area. Under the unsolicited interference measurement mechanism, the serving base station BS41 directly initiates interference measurement without receiving a request from the mobile station.

In one embodiment, the mobile station cannot distinguish whether the received signal is from a serving base station or another interfering station. In order to make the interference measurement of the mobile station more convenient, the serving base station BS41 does not transmit data signals on a given time-frequency region. As a result, the total signal power received by each mobile station over a given time-frequency region is equal to the total received interference power and can therefore be easily measured. In another embodiment, the mobile station can resolve the interference signal and the data signal, so the total received interference power, SIR, or SINR can be measured and calculated. For example, in a wireless communication system, such as a Worldwide Interoperable Microwave Access (WiMAX) system, the pilot signal emitted by each base station is translated into a unique code. Therefore, the mobile station can use the preamble signal power received from the serving base station to derive the interference power received from the interfering base station.

Figures 6A and 6B show schematic diagrams of the spontaneous interference measurement mechanism used in unit 40 of a cellular OFDMA system, where 48A, 48B are mobile station action content. The serving base station BS41 periodically broadcasts resource allocation messages to all mobile stations located within unit 40. In one embodiment, the mobile stations MS42, MS43, and MS44 decode the resource allocation message to obtain a time-frequency region (e.g., 48A) in which no signal is transmitted in each of the frame areas of the serving base station BS41. Next, each mobile station allocates a given time-frequency region within each frame region from the ground to perform interference measurements (eg, 48B). For example, a given time-frequency region is a subset of the decoding time-frequency region in which a serving base station BS41 does not transmit a signal. In another embodiment (not shown in Figures 6A and 6B), each mobile station will suggest which time-frequency region the serving base station BS 41 should be designated to perform interference measurements.

In a cellular OFDMA system, there are many different methods of measuring the interference statistics of a mobile station using a measurement module. In the present invention, the measurement module for measuring interference statistics (for example, the measurement module 27 in FIG. 3A) may be a programmable or non-programmable hardware or embedded in a mobile station. software.

Figure 7A shows a schematic diagram of various examples of measuring interference statistics at the mobile station MS42 of the cellular OFDMA system unit 40. In the example of Fig. 7A, the mobile station MS 42 is served by the serving base station BS 41 and is within reach of the adjacent interfering base station BS 45. As shown in Fig. 7A, if the mobile station can resolve the data signal and the interference signal, the interfering base station BS45 transmits an interference signal 46 to the mobile station MS42, and the serving base station BS41 can also transmit the data signal 47 to the mobile station MS42. In the first example, the mobile station MS42 obtains the interference power by measuring the reference signal power (e.g., the preamble power) of each base station, and the reference signal power is proportional to the total received power. In the second example, the mobile station MS 42 receives the interference signal 46 and identifies the precoding matrix index used by the interfering base station BS45. In the third example, the mobile station MS 42 resolves the data signal 47 and the data signal 46 and measures the SIR or SINR received by the mobile station MS 42. Figure 7B is a schematic diagram of the carrier of the signal. The signal includes a data carrier and a pilot carrier.

After the statistic of the interference signal is measured at the mobile station, the corresponding interference measurement result is obtained. The interference measurement results can be the same as the measured interference statistics. Interference measurements can also be calculated indirectly from interference statistics. In an embodiment, the interference measurement result is represented by an indicator identifying the interfering base station. If the mobile station can identify the signal of a particular interfering base station from the total received interfering signal, it then reports an indicator associated with at least one base station that caused the most significant interference. For example, this indicator relates to the lowest SINR, the strongest interference power, or other interference information. The specific interfering base station is selected by the mobile station from all interfering base stations (except the service base station). In general, a particular interfering base station is selected and rewarded by the mobile station. However, in some cases, the service base station may instruct the mobile station to report a particular interfering base station.

In another embodiment, the interference measurement results are represented by an indicator that identifies a preferred and non-preferred radio resource region, wherein the radio resource region is calculated based on the measured interference statistics. Because the interference statistics of the mobile station in different time-frequency regions may also vary considerably, the mobile station can collect different interference statistics by repeating the interference measurements in different time-frequency regions. After collecting interference statistics at different time-frequency regions, the mobile station may select an indicator that identifies the preferred or non-preferred radio region. For example, a preferred radio zone may be identified by the highest SINR or lowest interference power, and a non-preferred radio zone may be identified by the lowest SINR or the highest interference power.

The interference measurement results from the actual interference measurements of the mobile station may reflect the dynamic network conditions and are more accurate than the interference power estimated by the geographic location or measured by the foregoing. Therefore, based on accurate interference measurement results, the service base station or other network elements (such as network operators, network controllers, or other similar units) can more effectively apply adaptive frequency reuse to achieve the next generation. Higher system capacity required by 4G wireless communication systems.

The wireless communication system of the present invention uses adaptive frequency reuse techniques and optimizes connection quality and system capacity based on interference measurement results. Adaptive frequency reuse is particularly suitable for cellular OFDMA systems because it has more flexibility in allocating time-frequency resources to different units. Under adaptive frequency reuse techniques, mobile stations are scheduled to be served by different radio resource regions and appropriate frequency reuse modes. In addition, adaptive frequency reuse further coordinates radio resource allocation, scheduling, power allocation, antenna configuration, and the use of channelized formats to further leverage system resources to improve system performance. In a cellular OFDMA system, adaptive frequency reuse can be achieved by centralized network control units or coordination between base stations.

FIG. 8 is a schematic diagram of a cellular OFDMA system 50 according to an embodiment of the present invention, wherein 49A and 49B are action contents of the centralized radio resource control unit 51. The cellular OFDMA system 50 includes a centralized radio resource control unit 51, a plurality of units 52-55, a plurality of serving base stations BS 56-59, and a plurality of mobile stations. In the example of Fig. 8, the centralized radio resource control unit 51 first receives interference measurement results (e.g., 49A) from the base stations BS56-59 (or directly from the mobile station). Then, the centralized radio resource control unit 51 determines the frequency reuse mode (such as 49B) and configures the radio resource allocation (such as 49C) according to the received interference measurement result and other network configuration indicators.

9A and 9B are schematic diagrams of a cellular OFDMA system 50 according to an embodiment of the present invention, wherein 60A and 60B are action contents of the serving base station BS56-59. In the example of Figure 9A, the serving base station BS56-59 first receives interference measurement results (e.g., 60A) from the mobile station. The service base station BS56-59 then communicates with each other based on the received interference measurement results and other network configuration parameters to determine the frequency reuse mode (e.g., 60B). In the example of FIG. 9B, the downlink frame of unit 54 is divided into three radio resource regions, and the frequency reuse factor 1/K is equal to 1, 1/2, and 1/4, respectively, to serve in the service unit 54. Three mobile stations.

Figure 10 is a flow chart showing the application of adaptive frequency reuse of a cellular OFDMA system according to an embodiment of the present invention. If the cellular OFDMA system has a centralized radio resource control unit, the centralized radio resource control unit receives interference measurement results from the serving base station (step 61). Conversely, if there is no centralized radio resource control unit, the serving base station receives interference measurement results from the mobile station (step 62). In step 63, the centralized radio resource control unit or the serving base station determines the frequency reuse mode according to the received interference measurement result. More specifically, the following items are determined: the number of radio resource regions assigned to each unit, the frequency reuse factor used for each radio resource region, and the time-frequency region for each radio resource region. In step 64, the centralized radio resource control unit or the serving base station configures the radio resource allocation in accordance with the determined frequency reuse pattern. More specifically, the following items are determined: the transmission power of each radio resource region, the configuration of the antenna for each radio resource region (such as beam pattern, precoding vector), and each radio resource. The channelized format of the region (such as the alignment rules for multiple cells).

The schematic diagram of the cellular OFDMA system shown in FIG. 8 to FIG. 10 and the application flow chart of the adaptive frequency reuse method are determined by the centralized radio resource control unit or the service base station, and the frequency reuse mode is determined according to The determined frequency reuse mode configures the radio resource allocation (steps 63 and 64), and this embodiment is merely illustrative of the invention and should not be construed as limiting the scope of the invention. Since there may be multiple service base stations in the same cellular OFDMA system, and for various reasons, in the case of a centralized radio resource control unit in the cellular OFDMA system, not all service base stations can interfere. The measurement result is transmitted to the centralized radio resource control unit. Therefore, there is a part of the radio resource allocation controlled by the centralized radio resource control unit, and another part of the radio resource allocation is performed by the coordination between the service base stations. situation. That is to say, the step of determining the frequency reuse mode and configuring the radio resource allocation according to the determined frequency reuse mode can be jointly performed by the control of the centralized radio resource control unit and the coordination between the adjacent service base stations. In the case of the foregoing description of the present invention, the specific operation of the present invention will be known to those skilled in the art, and the details thereof will not be described herein.

In order to make the decision of the frequency reuse mode more convenient, the mobile station measures the interference statistics in different radio resource regions in accordance with the corresponding frequency reuse factors. In one embodiment, each mobile station measures the interference power or SINR it receives on different radio resource regions, and then reports the measured interference power or SINR to its serving base station. The centralized radio resource control unit receives the measured interference power or SINR, and then determines the frequency reuse pattern according to the number of mobile stations in each unit and the interference frequency or SINR of each mobile station in different radio resource regions. In one example, the frequency reuse mode is determined to minimize the average interference power, or the interference power of each mobile station is compared to a predetermined threshold (eg, the interference power of each mobile station is less than a predetermined threshold) ). In another example, the frequency reuse mode is determined to maximize the average SINR or to compare the SINR of each mobile station to a predetermined threshold (eg, the SINR of each mobile station is above a predetermined threshold) .

11A, 11B and 11C show an embodiment in which the cellular OFDMA system 50 determines the antenna configuration based on the received interference measurement results, wherein 70A and 70B are base station action contents; 70C is mobile station action content. ; 70D is the action content of the centralized radio resource control unit. In the examples shown in Figs. 11A, 11B, and 11C, the base station BS56 initially uses the precoding matrix indicator #K to serve the mobile station MS 68 (e.g., 70A). Under the adaptive frequency reuse technique, the mobile station MS69 performs the interference measurement (such as 70B) requested by the serving base station BS57 and reports the interference measurement result (for example, the precoding matrix indicator #K used by the interference base station BS56) (e.g., 70C). The base station BS 57 then communicates with the centralized radio resource control unit 51 the interference measurement result. Since the mobile station MS69 is very close to the MS 68, the MS 69 is strongly interfered by the precoding matrix indicator #K used by the interfering base station BS56. As a result, the base station BS 57 requests the base station BS 56 to change its beam pattern through the centralized radio resource control unit 51 to reduce strong interference (e.g., 70D).

Figure 12 shows an embodiment in a cellular OFDMA system 50 that determines a channelized format based on received interference measurements, where 71 is a local physical subcarrier; 72 is a fixed permutation; 73 is an interlaced entity Carriers; 74 are randomly arranged; 75 is inter-unit coordination; and 76 is interference randomization. In a localized channelization procedure, the physical subcarriers of each logical channel are distributed in local regions in the frequency domain. The channelized subcarrier arrangement in the different units remains the same. As a result, interference from a particular source of interference can be very significant. In an interleaved channelization procedure, the physical subcarriers of each logical channel are interleaved in the frequency domain. The channelized physical subcarrier arrangement of different units differs with a random-like approach. Therefore, interference from a particular source of interference is randomized. In general, the centralized radio resource control unit 51 can coordinate interference between units using a local channelization method. However, if the interference is too dynamic and difficult to coordinate, then the serving base station simply randomizes all signals in the particular radio resource region to exploit the interleaved channelization method to achieve the effect of interference randomization. The interference measurement results help the cellular OFDMA system to control or mitigate inter-cell interference using different channelization methods or mixed channelization methods.

FIG. 13 is a schematic diagram of a cellular OFDMA system 80 according to an embodiment of the present invention, wherein 89A is downlink control; 89B is uplink control; and 90 is action content of the base station. The cellular OFDMA system 80 includes a unit 81, a serving base station BS82 serving the unit 81, and mobile stations MS83 and MS84 located in the unit 81. The service base station BS82 will receive the interference measurement result of the mobile station (such as 89A) in the downlink FFR control or the interference statistics (such as 89B) in the uplink FFR control. The serving base station BS82 will then schedule the mobile station with the results of the interference measurements to service the appropriate radio frequency region (e.g., 90).

Figure 14 is a flow chart of the scheduling of the mobile station based on the results of the interference measurement to be served by the appropriate radio frequency region. In downlink FFR control, the serving base station instructs each mobile station to measure its interference statistics for a given time-frequency region under different radio resource regions (step 91). In step 92, the serving base station receives the interference measurement results returned by each mobile station. In step 93, the serving base station schedules each mobile station to be served by an appropriate radio resource region using a corresponding frequency reuse factor to optimize network performance. In the uplink FFR control, the serving base station measures its own interference statistics (step 94). In step 95, the serving base station communicates interference measurement results with other base stations or centralized network control units. At step 96, based on the interference measurement results, the adaptive frequency reuse pattern is determined by the coordination between the serving base station itself or by the base station.

15A, 15B, and 15C are schematic diagrams of data transmission schedules based on interference measurement results in the cellular OFDMA system 80, wherein FIG. 15B is a radio resource map for the serving base station BS82; 15C is a radio resource map for interfering with the base station BS85; 97 is the action content of the mobile station; and 98 is the action content of the base station. The cellular OFDMA system 80 includes an interfering base station BS85 that serves adjacent units 81. In the example of Fig. 15A, the physical structure 86 is located between the mobile station MS84 and the interfering base station BS85. If the mobile station MS83 uses a high frequency reuse factor (1/K equals 1) and the mobile station MS84 uses a low frequency reuse factor (1/K equals 1/3), the mobile station MS83 will receive the interference base. The station BS85 has a strong interference signal 87, and the mobile station MS84 does not receive an interference signal. Conversely, if the mobile station MS83 uses a low frequency reuse factor (1/K equals 1/3) and the mobile station MS84 uses a high frequency reuse factor (1/K equals 1), the mobile station MS83 does not receive interference. The interference signal of the base station BS85, and the mobile station MS84 also receives only the weak interference signal 88 after being blocked by the physical structure 86. Therefore, based on the interference measurement result (such as 97) reported by the mobile station MS83 and the mobile station MS84 to the serving base station BS82, the BS82 schedules the mobile station MS83 to serve the radio resource region with the frequency reuse factor 1/K equal to 1/3. And the scheduling mobile station MS84 serves a radio resource region (such as 98) whose frequency reuse factor 1/K is equal to 1. The dynamic frequency reuse is determined according to the interference measurement result of each mobile station, and the radio resources can be effectively allocated to achieve a balance between high system capacity and good service quality.

Figure 16A is a schematic diagram of simultaneous application of adaptive frequency reuse and uplink power control through base station coordination based on interference measurement results. If the target interference-to-interference (IoT) level of the radio resource area of other units is low, the mobile station assigned to this radio resource area will be instructed to transmit at a lower power to avoid affecting other The user of the unit. On the other hand, if the target interference noise ratio level of the radio resource regions of other units is high, the mobile station allocated to this radio resource region may allow transmission at a higher power. In order to control the interference of the whole system, the service base station will coordinate with other base stations to adjust the proportion of resource division and the corresponding target interference noise ratio level. Similarly, Figure 16B shows a schematic diagram of SINR based on uplink power control, where different target SINR levels specify different radio resource regions.

While the present invention has been described above by way of a preferred embodiment, it is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

1. . . Honeycomb type OFDMA system

2. . . unit

3. . . unit

4. . . Service base station

5. . . Service base station

6. . . Mobile station

7. . . Mobile station

8A. . . Base station action content

8B. . . Base station action content

9A. . . Base station action content

9B. . . Base station action content

10. . . Honeycomb type OFDMA system

11. . . unit

12. . . Service base station

13. . . Interference base station

14. . . Physical structure

15. . . Relatively strong interference signal

16. . . Relatively weak interference signal

17. . . Mobile station

18. . . Mobile station

19A. . . Mobile action content

19B. . . Mobile action content

19C. . . Base station action content

20. . . Honeycomb type OFDMA system

twenty one. . . unit

twenty two. . . Service base station

twenty three. . . Mobile station

twenty four. . . Mobile station

25. . . Mobile station

26. . . transceiver

27. . . Measurement module

28. . . Analogous fundamental frequency circuit

29. . . Digital baseband circuit

30. . . Memory

31. . . step

32. . . step

33. . . step

34. . . step

35. . . step

39A. . . Mobile action content

39B. . . Base station action content

39C. . . Given time-frequency region

40. . . unit

41. . . Service base station

42. . . Mobile station

43. . . Mobile station

44. . . Mobile station

45. . . Interference base station

46. . . Interference signal

47. . . Data signal

48A. . . Mobile action content

48B. . . Mobile action content

49A. . . Centralized radio resource control unit action content

49B. . . Centralized radio resource control unit action content

50. . . Honeycomb type OFDMA system

51. . . Centralized radio resource control unit

52. . . unit

53. . . unit

54‧‧‧ unit

55‧‧ units

56‧‧‧Service base station

57‧‧‧Service base station

58‧‧‧Service base station

59‧‧‧Service base station

60A‧‧‧Service Base Station Action Content

60B‧‧‧Service Base Station Action Content

61‧‧‧Steps

62‧‧‧Steps

63‧‧‧Steps

64‧‧‧Steps

68‧‧‧Mobile

69‧‧‧ mobile station

70A‧‧‧Base station action content

70B‧‧‧Base station action content

70C‧‧‧ action table action content

70D‧‧‧Centralized Radio Resource Control Unit Action Content

71‧‧‧Local physical subcarriers

72‧‧‧Fixed arrangement

73‧‧‧Interlaced physical subcarriers

74‧‧‧ Randomly arranged

75‧‧‧ Randomization

76‧‧‧Inter-unit coordination

80‧‧‧Hive-type OFDMA system

81‧‧‧ unit

82‧‧‧Base station

83‧‧‧ mobile station

84‧‧‧Mobile

85‧‧‧Base station

86‧‧‧ entity structure

87‧‧‧ Strong interference signal

88‧‧‧Weak interference signals

89A‧‧‧Downlink control

89B‧‧‧Upstream control

90‧‧‧Base station action content

91‧‧‧Steps

92‧‧‧Steps

93‧‧‧Steps

94‧‧‧Steps

95‧‧‧Steps

96‧‧‧Steps

97‧‧‧ action table action content

98‧‧‧Base station action content

FIG. 1 is a schematic diagram of a cell structure of a cellular OFDMA system of the prior art.

2A and 2B are schematic diagrams of FFR used in a cellular OFDMA system by the prior art.

3A and 3B are schematic diagrams of a cellular OFDMA system in accordance with an embodiment of the present invention.

Figure 4 is a flow chart of measuring interference statistics and reporting interference results in a cellular OFDMA system.

5A and 5B are schematic diagrams of the requested interference measurement mechanism and the unsolicited interference measurement mechanism used in the unit of the cellular OFDMA system.

6A and 6B are schematic diagrams of a spontaneous interference measurement mechanism used in a unit of a cellular OFDMA system.

Figure 7A is a schematic diagram of a mobile station located in a cellular OFDMA system unit.

Figure 7B is a schematic diagram of the carrier of the signal.

FIG. 8 is a schematic diagram of a cellular OFDMA system according to an embodiment of the present invention.

9A and 9B are schematic diagrams of a cellular OFDMA system according to an embodiment of the present invention.

FIG. 10 is a flow chart showing an application of adaptive frequency reuse of a cellular OFDMA system according to an embodiment of the present invention.

11A, 11B, and 11C are diagrams showing an embodiment of determining an antenna configuration based on received interference measurement results in a cellular OFDMA system.

Figure 12 is a diagram showing an embodiment of a channelized format based on received interference measurement results in a cellular OFDMA system.

Figure 13 is a schematic diagram of a cellular OFDMA system 80 in accordance with one embodiment of the present invention.

Figure 14 is a flow chart of the scheduling of the mobile station based on the results of the interference measurement to be served by the appropriate radio frequency region.

15A, 15B, and 15C are schematic diagrams of a scheduler based on interference measurement results in a cellular OFDMA system 80.

Figure 16A is a schematic diagram of simultaneous application of adaptive frequency reuse and uplink power control through base station coordination based on interference measurement results.

Figure 16B shows a schematic diagram of SINR based on uplink power control.

19A. . . Mobile action content

19B. . . Mobile action content

19C. . . Base station action content

20. . . Honeycomb type OFDMA system

twenty one. . . unit

twenty two. . . Base station

twenty three. . . Mobile station

twenty four. . . Mobile station

25. . . Mobile station

26. . . transceiver

27. . . Measurement module

28. . . Analogous fundamental frequency circuit

29. . . Digital baseband circuit

30. . . Memory

Claims (22)

A method for providing interference measurement results, using at least one mobile station to assist a cellular orthogonal frequency division multiple access system to enable frequency reuse, the method comprising: (a) transmitting a interference amount by a mobile station Requesting a request to a serving base station and thus receiving an interference measurement indication, wherein the interference measurement indication provides a given time-frequency region; (b) using the mobile station to implement an interference amount over the time-frequency region Measured to obtain an interference measurement result in the cellular orthogonal frequency division multiple access system, wherein the mobile station is located in a unit served by the service base station; and (c) report the interference measurement The result is given to the service base station. The method for providing an interference measurement result according to claim 1, wherein the interference measurement result is derived from an interference statistic calculated by the interference measurement, and wherein the interference measurement result includes a Interference power, a signal to interference ratio, a signal to interference plus noise ratio, a first indicator indicating an interfering base station, or a second indicator indicating a radio resource region. A method for providing interference measurement results, using at least one mobile station to assist a cellular orthogonal frequency division multiple access system to enable frequency multiplexing, the method comprising: by the at least one mobile station on a time-frequency region Performing a dry measurement to obtain an interference measurement result in the cellular orthogonal frequency division multiple access system, wherein the mobile station is located in a unit served by a service base station; Wherein the measurement in (a) comprises: measuring signal power received from the one or more interfering base stations over the time-frequency region, wherein the mobile station does not receive the signal from the time-frequency region The signal of the service base station; and (b) reporting the interference measurement result to the service base station. The method for providing an interference measurement result according to claim 1, wherein the measurement in (b) comprises: measuring a reference signal power of one or more interference base stations, wherein the service The base station transmits signals on the time-frequency region. The method for providing interference measurement results according to claim 1, wherein the measurement in (b) comprises: the mobile station distinguishing signals from the service base station and from one or more interference bases. The signal of the station, wherein the service base station transmits signals on the time-frequency region. The method for providing an interference measurement result according to claim 2, wherein the first indicator includes one or more indicator values, and the one or more indicator values are one or more of the interference base station Pre-code vector correlation. The method for providing an interference measurement result according to claim 2, wherein the second indicator comprises: an index value indicating a preferred radio resource region and a non-preferred radio region; At least one of an indicator value, wherein the preferred radio zone is defined by a highest signal to interference plus noise ratio or a lowest interference power, and wherein the non-preferred radio resource region is caused by the lowest signal and interference plus noise Defined than the highest interference power. Used to provide interference measurement as described in item 1 of the patent application. The method of the present invention, wherein the time-frequency region is obtained based on radio resource allocation information broadcasted by the serving base station. The method for providing an interference measurement result according to claim 1, further comprising: (d) receiving an interference measurement indication from the service base station, wherein the interference measurement indication indicates the time - Frequency area. A mobile station for providing interference measurement results, assisting a cellular orthogonal frequency division multiple access system to enable frequency multiplexing, the mobile station comprising: a transceiver for transmitting an interference measurement request to a network a channel unit for receiving an interference measurement indication, wherein the interference measurement indication provides a given time-frequency region; and a measurement module, the measurement module is configured by the honeycomb orthogonal division frequency An interference measurement is implemented in the access system, and an interference measurement result is obtained according to which the mobile station reports the interference measurement result to the network unit. The mobile station for providing interference measurement result according to claim 10, wherein the interference measurement result is obtained by calculating an interference statistic calculated by the interference measurement, wherein the interference measurement result is obtained. The method includes an interference power, a signal to interference ratio, a signal to interference plus noise ratio, a first indicator indicating an interference base station, or a second indicator indicating a radio resource area. The mobile station for providing interference measurement results according to claim 10, wherein the network unit is a service base station serving the mobile station. The mobile station for providing interference measurement results according to claim 12, wherein the measurement module is in a given time-frequency region The interference measurement is performed on the domain, and wherein the serving base station does not transmit signals on the time-frequency region. The mobile station for providing interference measurement results according to claim 12, wherein the measurement module performs the interference measurement on a given time-frequency region, and wherein the service is When the base station transmits a signal on the given time-frequency region, the measurement module further identifies at least one interference signal from a particular interfering base station. The mobile station for providing interference measurement result according to claim 10, wherein the measurement result further comprises a first indicator of the interference base station. The method for providing an interference measurement result according to claim 3, wherein the interference measurement result is obtained from the interference statistics calculated by the interference measurement, wherein the interference measurement result includes an interference power, and Signal to interference ratio, a signal to interference plus noise ratio, a first indicator indicating an interfering base station, or a second indicator indicating a radio resource area. A method of providing an interference measurement result as described in claim 3, wherein the time-frequency region is provided by an interference measurement indication from the service base station. The method for providing an interference measurement result according to claim 3, wherein when the service base station does not receive any interference measurement indication, the time-frequency zone is allocated by the radio resource broadcasted by the service base station. Obtained by the message. A method for providing an interference measurement result via a mobile station to assist in enabling frequency multiplexing of a cellular orthogonal frequency division multiple access system, the method comprising: Receiving an interference measurement indication from the service base station; measuring, by the mobile station, a interference measurement on a time-frequency region, and obtaining the interference measurement result of the cellular orthogonal frequency division multiplexing access system Wherein the mobile station is located in a unit of the service base station service; and reporting the interference measurement result to the service base station for enabling the frequency reuse, wherein the interference measurement result is from the interference amount Obtained in the measurement, and the interference measurement is calculated by an interference statistic, and wherein the interference measurement result includes an interference power in the time-frequency region. The method of claim 19, wherein the interference measurement result further comprises an indicator of an interfering base station, and wherein the indicator is related to one or more precoding vectors of the interfering base station. The method of claim 19, wherein the interference measurement result is used to adapt to frequency reuse, and wherein the frequency reuse mode is obtained by comparing the interference power with a threshold value. The method of claim 19, further comprising: transmitting, by the mobile station, an interference measurement request to the serving base station; and receiving an interference measurement indication from the service base station, wherein the interference measurement The indication provides a given time-frequency region.