RU2446635C2 - Wireless communication system - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: terminal measures wireless channel quality for each frequency band and notify base station about quality; base station determines frequency band to be used by terminal based on terminal notification. Then the terminal is grouped depending on difference and so on in frequency band in which the terminal is working, and notified to which terminal group it belongs; upon receiving notification from base station the terminal establishes its own and terminal group available frequency band and measures notified value of channel quality of available frequency band; measurement result is reported to the base station; the base station performs planning process for each available frequency band based on wireless channel quality of available frequency band of terminal and starts communicating with the terminal.

EFFECT: providing wireless communication system which capable to speedup planning process in base station.

16 cl, 32 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a wireless communication system.

State of the art

A mobile communication system that uses a scheduler to schedule a transfer, such as the HSDPA (High-Speed Downlink Packet Access), a 3GPP (3rd Generation Partnership Project, 3rd Generation Partnership Project) standard, has been partially launched for practical use.

The following describes an example of an HSDPA system for performing high speed downlink using an example terminal configuration and an example base station configuration.

Figures 1-5 are exemplary images of a conventional HSDPA system.

For example, in the terminal shown in FIG. 1, the wireless channel quality measurement / calculation module 13 measures and calculates the value of the wireless channel quality indicator (hereinafter referred to as CQI (channel quality indicator)) based on the downlink pilot signal received via the antenna 10, the radio module 11 and the demodulation / decoding module 12. As a practical example, the SIR (signal-to-interference ratio) is calculated by measuring the receive power and the interference power in the pilot signal. The CQI value is inserted into the transmitted signal by the wireless channel quality indicator transmission module 14, encoded and modulated by the coding / modulation module 15, and transmitted to the base station via the outgoing wireless channel via the antenna 10.

On the other hand, the base station shown in FIG. 2 receives a signal carrying a CQI value transmitted from a terminal through an antenna 20, a radio module 21 and a demodulation / decoding module 22, collects a wireless channel quality indicator (CQI) and notifies the scheduler 24 of the indicator . Scheduler 24 calculates the terminal priority for each available frequency band using the value of the wireless channel quality indicator (hereinafter referred to as CQI (channel quality indicator)), reported from the terminal, and selects transmission parameters based on the highest priority. The control signal generating unit 25 generates a transmitted control signal and transmits it to the terminal through the coding / modulation unit 27, the radio module 28 and the antenna 20. The transmission data from the transmission data buffer 26 is transmitted to the terminal after the control signal is transmitted.

Figure 3 is a block diagram of a planning process.

Suppose that in a cell of a base station there are terminals UE1 through UEn. At step S10, CQI values are received (CQI1 through CQIn). In step S11, values CQI1 through CQIn are stored. At step S12, the transmission time interval (hereinafter, TTI (transmission time interval)) is initialized. TTI is short-lived at a time interval and refers to a data transmission interval to a terminal. In this example, it is used as a variable indicating the transmission frequency. In step S13, the TTI value is increased by 1. In step S14, the priority Pk of the terminal UEk is calculated. In step S15, the system is initialized with values i = 0, j = 1. In step S16, the wireless resources Ri are calculated. When i = 0, wireless resources are not assigned. Therefore, Ri applies to all wireless resources. In step S17, it is determined whether or not the value of the wireless resources Ri is greater than 0. If at step S17 is YES, then control proceeds to step S21. If there is NO in step S17, then in step S18, from the n-i terminals, the value of the terminal UEj having priority Pk of the maximum value Pk_max is calculated. At step 19, a data transmission method (data block length, modulation system, etc.) to the terminal UEj is selected. In step S20, the values of the variables i and j are increased by 1, and control returns to step S16. In step S21, the control signal is modulated by the transmission method selected in step 19, and the result is transmitted to the terminal. In step S22, the transmission data is modulated for the terminal to which the control signal has been transmitted, the result is transmitted to the terminal, and the control returns to step S13.

To calculate the priority, the MAX CIR method for selecting a wider CQI value and the proportional fairness (PF) method are used to select a wider CQI for making equal opportunities.

The 3GPP standard mentioned above considers the specification of the E3G system (evolved 3-d generation, developed 3rd generation) as the next generation mobile communication system. In this specification, the OFDM (Orthogonal Frequency Division Division Multiplexing) and SC-FDMA (Single-Carrier Frequency-Division Multiple Access) systems for respectively are proposed for the multiple connection method for respectively data streams to the subscriber and data streams from the subscriber.

In addition, in the E3G system, the planning process is carried out in the same way as in the HSDPA system, but using a wider frequency band than the usual HSDPA (for example, four times). In addition, the terminal used in the E3G system has a different bandwidth for streams from and to the subscriber. In addition, in the flow to the subscriber, the bands available to the terminals depend on each terminal, for example, 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, 20 MHz, etc.

Therefore, it is necessary to carry out the planning process on a system band of 20 MHz, taking into account the available bandwidth.

That is, as shown in FIG. 4, it is necessary to carry out the planning process for the entire system using only one scheduler.

In addition, suppose that the downstream system bandwidth is 20 MHz and the downstream terminal bandwidth is 5 MHz. At the same time, the frequency used in transmission varies with the relationship with other terminals in accordance with four different options. Therefore, in order to allow the base station planner to select the optimal band among the plurality of available bandwidths taking into account the presence of other terminals, the CQI value for each 5 MHz band is measured and calculated at the terminal shown in FIG. 5, and the result is reported to the base station.

That is, compared with the HSDPA system, four times as many measurements and calculations are required. In addition, the frequency at which the CQI values are reported to the base station is quadrupled. As a result, the uplink interference is also quadrupled.

In the E3G system, when planning the entire system is carried out by one scheduler, then

- If you simply compare with the scheduler a typical HSDPA system, the number of terminals for planning increases at times (for example, four times).

- The size of the interval is 1/4 compared to the transmission interval of 2 ms in a typical HSDPA system, that is, 0.5 ms.

Due to the two above-mentioned reasons, the planning speed is required 16 times higher than in a typical system. That is, the priority calculation time is set to 1/16.

On the other hand, the improvement in the performance of central processing units (CPUs) and signal processing processors (DSPs), which carry out the planning process, from the data for 2010 is approximately four times higher than when the E3G system appeared, and this figure is very far from the above 16 times, given Moore’s law (processing speed doubles every 18 months).

Therefore, it is inevitable that the planning process is carried out at higher speeds.

Patent Document 1 describes the technology of grouping and planning processes for terminals moving at high speed. Additionally, it defines the frequency bands for which scheduling is required. It is assumed that they are based on HSUPA (high speed uplink packet access) 3GPP. However, in descriptions, a terminal moving at low speed or during stops does not need to be planned.

Patent Document 2 describes an example using OFCDM (Orthogonal Frequency and Code Division Multiplexing, orthogonal frequency and code division multiplexing). That is, the propagation process is performed in the frequency and time directions, after which the multiplexing operation is performed.

Patent Document 3 divides the terminals into groups based on the amount of attenuation of the transmission energy. Due to the lack of information on available frequency bands, it is assumed that conventional OFDM is used.

Patent Document 4 discloses principles for detecting a base station's speed of a mobile station using the Doppler frequency and the optimal choice of coding rate and modulation system.

Patent document 5 discloses the most optimal way to determine the transmission rate when communicating between the mobile station and the base station in accordance with information about the Doppler frequency, etc. from the mobile station.

Patent Document 6 discloses a method for grouping a subcarrier, obtaining channel quality information for each group, and transmitting and receiving this information.

Patent Document 1: Japanese Patent Application Laid-Open No. 2006-060814

Patent Document 2: Japanese Patent Application Laid-Open No. 2005-318434

Patent Document 3: Japanese Patent Application Laid-Open No. 2001-036950

Patent Document 4: Japanese Patent Application Laid-Open No. 2003-259437

Patent Document 5: Japanese Patent Application Laid-Open No. 2005-260992

Patent Document 6: Japanese Patent Application Laid-Open No. 2005-160079

Description of the invention

An object of the present invention is to provide a wireless communication system capable of expediting a scheduling process at a base station.

According to the present invention, a wireless communication system having a base station communicating with a plurality of slave terminals using a plurality of frequency bands includes: a grouping device assigning a plurality of terminals to a group of specific frequency bands in accordance with the quality of the wireless channel obtained for each band the frequencies used by the terminal to communicate with the base station; a scheduling device for scheduling grouped terminals for each group; and a communication device for a base station communicating with the terminal in accordance with the result of scheduling.

Brief Description of the Drawings

Figure 1 shows an exemplary view (1) of a typical HSDPA system;

Figure 2 shows an exemplary view (2) of a typical HSDPA system;

Figure 3 shows an exemplary view (3) of a typical HSDPA system;

Figure 4 shows an exemplary view (4) of a typical HSDPA system;

Figure 5 shows an exemplary view (5) of a typical HSDPA system;

Figure 6 shows the sequence of processes in the system when implementing the described invention;

Fig. 7 is an exemplary view illustrating a case in which a grouping operation is performed by the easiest method based on the channel quality of each band in the process of setting channel settings;

FIG. 8 illustrates an image of a wireless channel quality measurement for each available bandwidth; FIG.

Fig. 9 is an exemplary view (1) explaining a method of grouping and scheduling a terminal;

10 is an exemplary view (2) explaining a method of grouping and scheduling a terminal;

Figure 11 presents an exemplary view of the image of the grouping and planning methods in the case when the available bandwidth of the terminal differs from that shown in Figure 10.

12 is an exemplary view (1) of a hierarchical grouping process;

On Fig presents an exemplary view (2) of the hierarchical grouping process;

Fig. 14 shows an example of a grouping table of a base station when a terminal is grouped;

On Fig presents an exemplary view of other grouping methods;

FIG. 16 shows an example of a grouping table of a base station for the grouping operation shown in FIG. 15.

17 is a view (1) of an example process when the terminal is grouped;

FIG. 18 is a view (2) of an example process when the terminal is grouped;

FIG. 19 is a view (3) of an example process when a terminal is grouped;

FIG. 20 is a view (4) of an example process when a terminal is grouped;

On Fig shows a view (5) of an example of a process when the terminal is grouped;

22 is a configuration view showing a principle of a terminal in accordance with the present invention.

23 is a configuration view showing a principle of a base station in accordance with the present invention.

On Fig shows an example configuration shown in Fig, in the application for the case when the CQI is measured as the quality of the wireless channel;

On Fig shows an example configuration shown in Fig, in the application for the case when the CQI is measured as the quality of the wireless channel;

On Fig shows a second example configuration of a base station in accordance with the implementation of the present invention;

On Fig shows a third example configuration of a base station in accordance with the implementation of the present invention;

On Fig shows a second example configuration of the terminal in accordance with the implementation of the present invention in accordance with Fig;

On Fig shows a fourth example configuration of a base station in accordance with the implementation of the present invention;

On Fig shows a fifth example configuration of a base station in accordance with the implementation of the present invention;

The best way to implement the invention

Descending gear is described below as an example.

6 is a sequence of steps in the implementation process of the present invention.

6, the terminal measures the quality of the wireless channel for each frequency band (1). The measurement is performed by calculating the SIR value based on the received data, and then using the calculated SIR value, the CQI value is obtained. The measured wireless channel quality value is reported to the base station (2). The base station determines the frequency band available for the terminal based on the received information about the quality of the wireless channel (3) and divides into groups (4) all the terminals that transmitted information about the quality of the wireless channel. When the grouping process is completed, the base station tells each terminal which terminal group it belongs to (5). Upon receiving notification of the terminal group, the terminal sets the value of the available frequency band and terminal group (6). The terminal measures the quality of the wireless channel on the available frequency band set for this terminal (7), and notifies the base station of the results (8) of the measurements. The base station implements a scheduling process for each available frequency band based on the notified wireless channel quality value. That is, the base station selects the transmission technology based on the priority of the terminal, and then selects the transmission method. After that, it generates control information to be received by the terminal, notifies the terminal of the transmission control information (10) and then transmits data (11).

Thus, in the OFDMA system (Orthogonal Frequency-Division Multiple Access, orthogonal frequency division multiple access) and the MC-CDMA (Multi-Carrier Code Division Multiple Access, multiple carrier division multiple access), the terminals are grouped according to availability available bandwidth and available specific frequencies. The grouping process can be carried out either when the wireless channel is installed, or at predetermined intervals after the establishment of the wireless channel. The information for the grouping process can be the possible bandwidth available for the terminal, the quality of the channel of each frequency, the use of the channel (download) of each frequency, etc.

7 explains and illustrates the case in which the grouping operation is carried out in the simplest way based on the channel quality of each band during channel setup.

In practice, we can consider the case in which the maximum available bandwidth of the terminal is 5 MHz, and the system has a bandwidth of 20 MHz. When the characteristic is set, the terminal measures the quality of the wireless channel for each band, the value of which is obtained by dividing the system bandwidth of the 20 MHz system by the maximum available 5 MHz bandwidth of the terminal, calculates the wireless channel quality indicator (1) and notifies the base station of the calculated indicator (2 ) The base station (or wireless channel control station) determines the available frequencies based on this information and the possible available bandwidth of the terminal (3), splits the terminal for each available bandwidth or frequency, and performs grouping (4). It is also possible to determine the available frequencies by considering channel loading between frequencies that can be adjusted.

Fig. 7 is basically the same as Fig. 6, but the available frequency bands and the terminal group are set when the channel is set, the quality of the wireless channel on the available frequency bands of each terminal is measured by each terminal in the normal state, the base station carries out the planning process based on received information about the quality of the wireless channel and begins to communicate. Normal operation is the same as in FIG. 6, therefore, a description has been omitted.

FIG. 8 illustrates an image of a wireless channel quality measurement for each available band.

As described above, the terminal for which the terminal group is defined measures the channel quality only for certain available frequencies, calculates the CQI and reports the results of the base station.

Thus, the number of messages with CQI is reduced, and therefore uplink interference is reduced.

The base station, which has adopted the CQI value, sets the CQI for each group of the terminal and performs the scheduling process for each terminal group (each available frequency band). Thus, due to the decrease in the number of terminals for which planning is necessary, the computational complexity of computing the priority of the terminal in the planning process is reduced, correspondingly increasing the speed of the overall process. Moreover, since the planning process is carried out for each terminal group, the overall process can be further accelerated by the parallel work of several planners.

Figures 9 and 10 are exemplary views of a method for grouping and scheduling a terminal.

9 and 10, the system bandwidth is 20 MHz, the terminal bandwidth is 5 MHz, and the UEs 100 to 139 are classified into four groups. Group 1 using frequency band 1 is scheduled by scheduler 1 of the four planners. In the same way, group 2 is assigned to frequency band 2 and scheduler 2, group 3 is assigned to frequency band 3 and scheduler 3, group 4 is assigned to frequency band 4 and scheduler 4. This is shown in FIG. 10 (a). Since the data transmission interval is 0.5 ms, the planning process for each group is carried out every 0.5 ms.

Thus, when multiple schedulers are provided, each terminal group is assigned to one scheduler. That is, the planning of group 1 is carried out, for example, by the scheduler 1, and the planning of group 2 by the scheduler 2. As shown in FIG. 10 (b), the planning process can be carried out in parallel.

11 is an exemplary view (1) of an image of grouping and planning methods in the case where the available bandwidth of the terminal differs from that shown in FIG. 10.

11, the available bandwidth of the terminal is 10 MHz, also shows group 5 scheduled by scheduler 5 using frequency bands 1 and 2, and group 6 planned by scheduler 6 using frequency bands 3 and 4.

12 and 13 are an exemplary view of hierarchical grouping.

As described above, the possible available bandwidth for the terminal depends on the performance of the terminal. Therefore, there may be a method for implementing the grouping process based on the possible available bandwidth. In the case illustrated in FIG. 12, terminals UE 160-169 capable of using a bandwidth of 20 MHz are assigned to group number 7, and they are scheduled by scheduler number 7. On the other hand, terminals UE 140-149 and terminals UE 150- 159, for which a bandwidth of 10 MHz is available, are assigned respectively to group 5, which is planned by the scheduler 5 using frequency bands 1 and 2, and to group 6, which is planned by the scheduler 6 using frequency bands number 3 and 4. Terminals UE 100-109, 110-119, 120-129 and 130-13 9, for which a bandwidth of 5 MHz is available, are assigned respectively to group 1, the planning of which is carried out by the scheduler 1 using the frequency band 1, to group 2, the planning of which is carried out by the scheduler 2 using the frequency band 2, to the group 3, the planning of which is carried out by scheduler 3 using frequency band 3, and to group 4, the planning of which is carried out by scheduler 4 using frequency band 4.

As shown in FIGS. 13 (a) and (b), it is assumed that all possible available frequency bands are used, and, for example, a group capable of operating in a wider bandwidth, for example 10 MHz, is considered as a group with a higher priority, and a group capable of operating in a narrower bandwidth, for example, 10 MHz is considered as a group with a lower priority. The planning process is carried out from groups with a higher priority to groups with a lower priority.

As shown in FIG. 13 (a), first every 0.5 ms (data transmission interval), group 7 is scheduled, then groups 5 and 6, and finally groups 1-4. Part (b) of FIG. 13 illustrates a hierarchical planning scheme. The planning process is carried out sequentially and hierarchically, starting with the scheduler 7. Due to the fact that two schedulers, namely the schedulers 5 and 6, as well as four schedulers, namely the schedulers from 1 to 4, work in parallel, we can expect an acceleration of the planning process.

Fig. 14 shows an example of a grouping table of a base station after grouping of terminals.

According to each terminal group number, the center frequency available to each group, the bandwidth and the identification number of the terminal belonging to each group are entered.

15 is an exemplary view of other grouping methods.

The required baud rate depends on the data to be transmitted. Therefore, the required frequency bandwidth also depends on the data. That is, for a guaranteed quality of service (hereinafter QoS, quality of service), you may need either a large bandwidth or an available bandwidth. In addition, if the transmission can be performed by narrowing the bandwidth for relations with other terminals, then the necessary transmission speed cannot be satisfied and the transmission can be carried out. Therefore, if the available frequency bandwidth is 20 MHz, it cannot belong only to the terminal group of 20 MHz, but also belong to terminal groups with a narrower bandwidth, such as 10 MHz, 5 MHz, etc. Thus, the terminal group is hierarchically determined in a decreasing order by the size of the available bandwidth. 15, a terminal having an available frequency band of 20 MHz can communicate at 10 MHz and 5 MHz. In addition, a terminal having an available frequency band of 10 MHz can communicate at 5 MHz. UE terminals from 160 to 169 with an available bandwidth of 20 MHz belong not only to group 7, which is scheduled by scheduler 7, but also to group 1 to 6. Accordingly, when UE 160-169 terminals cannot use the 20 MHz band, they can be assigned to groups 5 or 6 having a bandwidth of 10 MHz. When they cannot use the 10 MHz band, they can be attached to any group with numbers from 1 to 4, whose bandwidth is 5 MHz. Thus, the likelihood that the terminals UE 160-169 will not be able to communicate can be reduced. Similarly, UE terminals from 140 to 149 and from 150 to 159, which have a 10 MHz frequency band available, can also be assigned to groups from 1 to 4, and thus, when it is not possible to communicate on a 10 MHz frequency band, these Communications can be made using the 5 MHz band. Terminals from 100 to 109, from 110 to 119, from 120 to 129 and from 130 to 139 belong only to groups from 1 to 4, because a frequency band of less than 5 MHz is not available.

The planning process is performed from groups with a higher priority (e.g., 20 MHz) to groups with a lower priority (e.g., 5 MHz). Thus, the number of terminals that need planning can be reduced in a group, the costs of the priority calculation process can also be reduced, which speeds up the overall planning process.

FIG. 16 illustrates an example grouping table at a base station for the grouping operation shown in FIG. 15.

The table contains the following data corresponding to terminal groups with numbers from 1 to 7: the center frequency of the available frequency band; The width of the line; terminal identification numbers that belong to each group.

In the case illustrated in FIG. 14, when multiple planners are provided, the number of planners must be equal to the number of groups. The planning process can be accelerated by assigning a planner for each group and ensuring the parallel and hierarchical functioning of several planners. In addition, multiple schedulers can be replaced by a single scheduler capable of performing multiple operations in parallel.

17-21 show examples of a process in which terminals are grouped.

In the example illustrated in FIG. 17, in step S30, the maximum available bandwidth for the terminal is confirmed. At step S31, the CQI value for each band is received from the terminal. In step S32, an available band is selected based on the maximum CQI value. In step S33, a terminal group corresponding to the selected band is selected.

In the example illustrated in FIG. 18, in step 35, the maximum available bandwidth of the terminal is confirmed, and in step S36, the CQI value for each band is received. In step S37, an available band is selected based on the CQI value and the load of each band, and in step S38, a terminal group is selected. The congestion of each lane refers to the number of terminals already assigned to each lane, etc. When the number of terminals assigned to a particular frequency band becomes too large, the frequency of the selection by the scheduler decreases, and the transmission speed becomes lower. In this case, the frequency selection process is not based on the highest CQI, but on the basis of the second largest CQI, etc.

In the example illustrated in FIG. 19, at step S40, the maximum possible available bandwidth of the terminal is confirmed. In step S41, bandwidth and CQI values for each band are received. In step S42, based on the maximum CQI value, an available bandwidth and an available band are selected. In step S43, a terminal group is selected. 19, a terminal may use several available bands. For example, when the system’s frequency band is 20 MHz and the terminal’s available frequency band is 10 MHz, the terminal can use both 10 MHz and 5 MHz. Therefore, the terminal measures CQI values for two 10 MHz wide bands and four 5 MHz wide bands, and the base station selects the available band based on the results of the change.

In the example illustrated in FIG. 20, a case is considered when a guaranteed bit rate (hereinafter GBR, guaranteed bit rate) Qo3 is set. That is, a case is considered in which a lower transmission rate regulation service is installed. For example, suppose a possible transfer rate is 3 Mbps and the code rate is 1/3. At the same time, with a GBR terminal of 5 Mbps, it is necessary that the bandwidth be 10 MHz to satisfy GBR. Therefore, the terminal must be assigned to a group with an available bandwidth of 10 MHz. As a modulation system, you can use QPSK (Quadrature Phase Shift Keying, quadrature phase modulation), as well as multi-position modulation systems 16 QAM (Quadrature Amplitude Modulation, 16-position quadrature amplitude modulation), 64 QAM (64-position quadrature amplitude modulation)) and etc., while the code rate can vary and the MIMO function (Multiple Input Multiple Output, multiple input / multiple output) can be used.

At step S45, the maximum available bandwidth of the terminal is confirmed. At step S46, the QoS of the data transmitted to the terminal is confirmed. At step 47, the necessary bandwidth is calculated. At step 48, CQI is received for each band of the desired bandwidth. In step S49, an available bandwidth is selected based on the maximum CQI, the possible available bandwidth and the necessary bandwidth. In step S50, a terminal group is selected.

In the example illustrated in FIG. 21, transmission degradation associated with terminal movement is considered. The level of degradation of transmission parameters is determined by the Doppler frequency, which in turn depends on the speed of the terminal. Since the Doppler frequency improves with increasing available frequencies, when communicating with the terminal, it is desirable to use a lower frequency, which corresponds to a high speed of movement.

For example, when the system bandwidth is 20 MHz and the center frequency is one of the frequencies f1 <f2 <f3 <f4 in FIG. 14, a terminal moving at a high speed uses a higher frequency band (with center frequencies f3, f4, and f6 ), and for a terminal moving at a low speed or stopped, a lower frequency band (f1, f2 and f5) is used.

Before grouping the terminal, it is necessary to evaluate its speed, which can be done either by the terminal itself or the base station. As an evaluation method, it is possible to use, for example, measuring the interval (attenuation frequency) of the drop in the intensity of reception of the electric field by the degree of attenuation. The result is compared with the threshold of the speed of movement, if the speed of movement is higher than the threshold, then high-speed movement is determined, if the speed of movement is lower than the threshold, then low-speed movement or a stop state is determined.

At step S55, the motion speed of the terminal is estimated. At step S56, the driving speed is determined: high or low. At step S57, the maximum available bandwidth is confirmed. At step S58, CQI values are obtained from the terminal for each band of the necessary bandwidth. In step S59, the bandwidth and the available frequency are selected for each lane based on the speed, possible available frequency, and CQI value. In step S60, a terminal group is selected.

On Fig presents the configuration of the main blocks of the terminal in accordance with this invention. On Fig presents the configuration of the main blocks of the base station in accordance with this invention.

The block numbers in Fig. 22 coincide with the numbers of the corresponding blocks in Fig. 1. The block numbers in Fig. 23 coincide with the numbers of the corresponding blocks in Fig. 2.

In downlink transmission in a wireless communication system, the use of several bands in an OFDMA system, such as E3G and MC-CDMA and others, is used in the following cases: when the terminal receives a downward control signal (for example, a pilot signal), when channel settings are set using antenna 10, radio module 11 and demodulation / decoding module 12, after which the quality of the wireless channel for each frequency is measured using the channel quality measuring module 13, and then it is communicated to the base station via the uplink when The module 14 for transmitting the channel quality value, the coding / modulation module 15, the radio module 16, and the antenna 10.

In the base station, which receives the wireless channel quality values for each band, the channel settings setting measurement extraction unit 29 retrieves the wireless channel quality value and other values measured by the terminal for each band, and transmits this data to the channel setting module 30. The channel setting module 30 accesses the terminal group setting module 31 for information about the terminal, analyzes the possible available bandwidth of the terminal, as well as the usage status and loading of the band, determines which band the terminal uses, assigns the terminal to a specific group based on the available band and informs the terminal the result through the terminal group tuning signal generation unit 32.

Upon receipt of the notification, the terminal allows the terminal group configuration information extraction module 17 to extract the configuration information, sets the frequency band, other parameters of the terminal group to which the terminal is assigned, in modules 11 and 16, as well as in the channel quality measurement module 13 through the control module 18 terminal settings. Subsequently, the channel quality of the available band is periodically measured by the channel quality measuring unit 13, the channel quality indicator is calculated, and the result is notified to the base station via the wireless output channel.

When the base station allows the channel quality information collection / classification module 23 to receive the value of the wireless channel quality indicator from each terminal, it sets the value of the wireless channel quality indicator for each group to which the terminal belongs, and calculates the transmission priority based on the wireless channel quality indicator for each group using planners from 24-1 to 24-n. At this stage, from the set of schedulers from 24-1 to 24-n, the scheduler is selected that is responsible for the group to which the terminal that transmitted the channel quality information belongs, and this scheduler calculates the transmission priority. In Fig. 23, only two schedulers are shown, but in the general case n schedulers can be used, and the greatest efficiency is achieved when the number of schedulers is equal to the number of terminal groups.

The terminal for transmission is selected based on the result of calculating the priority, after which the transmission method is selected (for example, the amount of transmitted data, modulation system, code rate, etc.), based on the selection results, a control signal is generated by modules 25-1 to 25-n transmission, and this signal is transmitted to a terminal that transmits data.

After sending the transmission control signal, the data for transmission is encoded by the selected transmission method, modulated, and then transmitted to the terminal. The transmission method is selected taking into account the possible available bandwidth of the terminal and the possible available modulation system.

In addition, by limiting the possible available modulation system for each group (for each scheduler), the process of selecting a transmission method can be simplified.

The terminal allows the control signal extraction module 19 to extract the transmission control signal transmitted from the base station, analyzes the signal content and makes the necessary settings for receiving data in the demodulation / decoding module 12. After tuning, the data transmitted from the base station is received.

As described above, by grouping terminals based on available bands, the following actions can be performed:

1) The quality of the wireless channel is measured only for the available band, the indicator of the quality of the wireless channel is calculated, and the result is reported to the base station.

2) The planning process is carried out for each group, calculated by priority, the transmitting terminal is selected and the transmitting method is determined.

As described above, this can achieve the following effect.

On unused bands, efforts to measure the quality of the wireless channel can be reduced. That is, this process can be carried out very easily. In addition, you can reduce the number of messages to the base station in which the indicator of the wireless channel is transmitted. Thus, the transmission process can be shortened at the terminal, the number of messages can be reduced, and therefore, wave interference with the uplink is reduced.

Moreover, since the planning process can be carried out for each group, the number of terminals for planning can be reduced and the processing time required to calculate the priority and other parameters can be reduced. Plus, by executing the planning process for each group, you can execute these processes in parallel, which reduces the processing time required to calculate the priority, etc.

In the base station configuration example shown in FIG. 23, the channel setting module 30 and the terminal group setting module 31 surrounded by a dashed line may be provided to the wireless channel control station (RNC) as an external flow device of the base station.

As described above, the terminals are grouped when the channel is installed, but the grouping process can be changed at predetermined intervals or to control the number of terminals in the corresponding frequency bands. In this case, for example, this process can be performed as part of the procedure shown in Fig.6.

Fig. 24 shows an example of the configuration discussed in Fig. 22, as applied to the case where CQI is measured to evaluate the quality of the wireless channel. Fig. 25 shows an example of the configuration discussed in Fig. 23, as applied to the case where CQI is measured to evaluate the quality of the wireless channel.

The CQI measurement / calculation module shown in FIG. 24 measures and calculates CQI only for the frequency band used for the corresponding terminal group after determining which group the given terminal belongs to. The necessary settings are set by the terminal settings management module 18. The CQI value collection / classification module 23 shown in FIG. 25 measures CQI values related to the available frequency bands of the terminal group to which the terminal belongs and receives the calculated value. The obtained CQI value is transmitted to the scheduler to carry out the planning process for the corresponding terminal group.

On Fig shows a second example configuration of a base station in accordance with the implementation of the present invention. The block numbers in Fig. 26 coincide with the numbers of the corresponding blocks in Fig. 23.

In the above configuration example, the grouping process is performed taking into account the possible available bandwidth of the terminal. In this example, the possible available frequency band of the terminal is 20 MHz, and the band after division is 5 MHz. The terminal is part of a group to which the 20 MHz band is available. However, depending on the type of data transmitted, the requested transfer rate may not require a bandwidth of 20 MHz. In this case, the use of a bandwidth of 20 MHz is impractical. However, for a group for which the available bandwidth is fixed, the available band is still 20 MHz.

Now suppose that the terminal is part of several groups having a bandwidth of 20 MHz, 10 MHz, and 5 MHz. Since the terminal can be part of groups having different available center frequencies, this terminal can be part of one of seven groups. In this case, when a wide frequency band is used and when the transmitting terminal is selected, the scheduling process is performed in a descending order of the available bandwidths. Using the hierarchical construction of groups in descending order of the available bandwidths, you can easily use a wide frequency band. In addition, when a wide band is used, it is desirable to select successive bands, since this facilitates the use of the hierarchical configuration described above.

At the time the hierarchical grouping is completed, the schedulers for each terminal group have not yet been assigned, but this can be done by using the hierarchical scheduler 24a, capable of performing parallel calculations.

On Fig shows a third example configuration of a base station in accordance with the implementation of the present invention. On Fig shows a second example configuration of a base station in accordance with the implementation of the present invention, corresponding to Fig. The block numbers in Fig. 27 coincide with the numbers of the corresponding blocks in Fig. 23. The block numbers in Fig. 28 coincide with the numbers of the corresponding blocks in Fig. 23.

In this case, uplink data transmission is described as an example, but based on the quality information of the uplink wireless channel, an available frequency band can be selected for downlink data transmission.

The terminal performance information generating unit 53 generates terminal performance information based on terminal performance data stored in the terminal performance data storage unit 52, and the terminal transmits a control signal (e.g., a pilot signal) generated by the module 54 as terminal performance information generating an uplink control signal 54 based on information about a possible available band.

The base station measures the input power of a control signal (eg, a pilot signal) transmitted from the terminal during channel setup using each band to the CQI measurement / calculation module 50, after which the terminal performance information extraction module 51 extracts the result obtained by calculating the wireless quality the channel of each strip and the possible available bandwidth of the terminal, then this data is transmitted to the channel tuning module 30, the group to which this terminal will enter is selected, and t The result is reported to the terminal.

Upon receiving this message, the terminal retrieves the group information through the group setting information extraction module 17, sets the settings of devices such as the radio modules 11 and 16 through the settings management module 18, and then performs uplink data transmission using the selected bands.

On the other hand, the base station, through the wireless channel quality indicator obtaining module 23, measures and calculates the quality of the uplink wireless channel only for the bands of the group the terminal belongs to and performs the planning process based on the measurement and calculation results. Based on the priority calculated during the planning process, a terminal is selected, then an upstream transmission method is selected, and the result is reported to the selected terminal. The message is retrieved by the terminal through the control signal extraction module 19, and the settings are set by the demodulation / decoding module 12.

On Fig shows a fourth example configuration of a base station in accordance with the implementation of the present invention. The block numbers in Fig. 29 coincide with the numbers of the corresponding blocks in Fig. 23.

In the above configuration, the selection of a group for the terminal is based on the quality of the wireless channel of each band and the possible available bandwidth. However, in this example, when choosing a group for the terminal, QoS (guaranteed quality of service) of the data for transmission is taken into account. Since by the time the station communicates with the terminal, the QoS is predetermined (for example, during channel setup), and the base station is informed about the QoS value in advance, it feeds this information to the input of the channel settings setup module 30 and the terminal group setup module 31, to take into account data about this terminal in the grouping process.

On Fig shows a fifth example configuration of a base station in accordance with the implementation of the present invention. The block numbers in Fig. 30 coincide with the numbers of the corresponding blocks in Fig. 23.

In the above configuration, the selection of a group for the terminal is based on the quality of the wireless channel of each band and the possible available bandwidth. However, in this example, the group selection process is performed taking into account the speed of the terminal. For example, at the base station, the motion velocity measurement / calculation module 40 measures a control signal (for example, a pilot signal) transmitted from the terminal and data input power, and, based on the measurement result, calculates the motion speed (or relative speed between the terminal and the base station) of the terminal .

In the terminal group setup module 31 or the channel settings setup module 30, the measured or calculated terminal speed is compared with a speed threshold whose value is stored in the terminal group setup module 31 of the channel settings setup module 30. If this speed is equal to or exceeds the threshold value, it is determined that the terminal is moving at high speed, the available bandwidth and available frequency, as well as the terminal group, are selected. The speed threshold value can be stored outside the terminal group setup module 31 and the channel settings setup module 30.

As described above, in accordance with this invention, the terminal is grouped for each available frequency, and its planning is carried out within the group, thereby reducing the number of end terminals that need planning, parallelizing the planning process and reducing the processing time required for the planning process.

In addition, since the quality of the wireless channel can only be measured for the available frequency band, the measurement process can be shortened. Further, since the number of channel quality messages can be reduced, this will successfully reduce interference power.

Claims (16)

1. A wireless communication system having a base station communicating with a plurality of slave terminals using a plurality of frequency bands, the base station comprising:
a terminal notifying with information about the measured value of the quality of the wireless channel;
a grouping device that assigns the terminals to a group in accordance with the available frequency band of the terminal, determined based on the quality of the wireless channel;
a scheduling device scheduling a grouped terminal for each group; and
a communication device for a base station communicating with a terminal in accordance with a scheduling result. 2. The system according to claim 1, in which the terminal is included in the group hierarchically depending on the level of the bandwidth of the frequency band used by the terminal for scheduling the terminal in a descending sequence of the hierarchical structure of the terminal groups. 3. The system according to claim 1 or 2, in which the terminal may belong to several groups. 4. The system according to claim 1, in which the base station can measure the quality of the wireless channel only in the frequency band of the group to which the terminal communicates. 5. The system according to claim 1, in which the terminal can measure the quality of the wireless channel only in the frequency band of the group to which the terminal belongs. 6. The system of claim 5, wherein the wireless channel quality indicator is obtained by calculating the measured wireless channel quality, and this indicator is transmitted to the base station. 7. The system according to claim 1, in which
the terminal calculates the quality of the wireless channel from the receiving power of the control signal transmitted from the base station during the installation of the channel, and transmits the result to the base station; and
the base station groups the terminal based on the received channel quality value and notifies the terminal of the group to which the terminal belongs. 8. The system according to claim 1, in which the base station calculates the quality of the wireless channel from the receiving power of the signal transmitted from the terminal during channel installation, groups the terminal based on the quality of the wireless channel, and notifies the terminal about the group to which it belongs. 9. The system according to claim 1, in which the terminal is additionally included in the group, taking into account the possible available bandwidth of each terminal. 10. The system according to claim 1, in which the base station further comprises a grouping device that assigns the terminals to the group in accordance with the quality of service information regarding data transmitted from or to the terminal. 11. The system according to claim 1, in which the terminal is additionally included in the group taking into account the measurement of the value of the speed of movement of this terminal. 12. The system according to claim 1, in which for each group a modulation system and a coding rate are set for use in communications. 13. The system of claim 1, wherein the scheduling device comprises a plurality of schedulers responsible for scheduling respective groups. 14. A wireless communication method in which a base station communicates with a plurality of slave terminals using a plurality of frequency bands, comprising:
assigning a plurality of terminals to a group in accordance with information on an available terminal bandwidth;
planning a grouped terminal for each group; and communicating with the base station with the terminal in accordance with the planning result. 15. A wireless communication system having a base station communicating with a plurality of slave terminals using a plurality of frequency bands, comprising:
a grouping device that assigns a plurality of terminals to a group in accordance with information on the available terminal bandwidth. 16. A wireless communication system having a base station communicating with a plurality of slave terminals using a plurality of frequency bands, comprising:
a grouping device that assigns a plurality of terminals to a group for each of the frequency bands in accordance with information about the available bandwidth of the terminal and the quality of the wireless channel obtained for each frequency band used by the terminal in communication with the base station;
a scheduling device scheduling a grouped terminal for each group; and
a communication device for a base station communicating with a terminal in accordance with a scheduling result.

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