Source: https://patents.google.com/patent/EP1239602B1/en
Timestamp: 2018-11-22 12:08:53
Document Index: 533746706

Matched Legal Cases: ['arts 31', 'arts 32', 'art 31', 'art 33', 'art 34', 'arts 101', 'arts 102', 'art 101', 'art 103', 'art 104', 'art 105', 'art 103', 'art 104', 'art 102', 'art 104', 'art 105', 'art 105', 'art 103', 'art 103', 'art 104', 'art 705', 'arts 1101', 'arts 1102', 'art 1101', 'art 1201', 'art 1206', 'art 1207', 'art 1201', 'art 1202', 'art 1203', 'art 1201', 'art 1204', 'art 1205', 'art 1208', 'art 1203', 'art 1205', 'art 1203', 'art 1203']

EP1239602B1 - Transmission power control apparatus, transmission power control method, and mobile station - Google Patents
Transmission power control apparatus, transmission power control method, and mobile station Download PDF
EP1239602B1
EP1239602B1 EP20020250327 EP02250327A EP1239602B1 EP 1239602 B1 EP1239602 B1 EP 1239602B1 EP 20020250327 EP20020250327 EP 20020250327 EP 02250327 A EP02250327 A EP 02250327A EP 1239602 B1 EP1239602 B1 EP 1239602B1
EP20020250327
EP1239602A3 (en )
EP1239602A2 (en )
In the following, conventional transmission power control in a wireless communication system adopting CDMA will be described. A wireless communication system shown in Fig.1 is taken as an example here. In the wireless communication system, a wireless network control station 1 controls a plurality of base stations 2, each base station 2 controls one cell 3 and the base station communicates with mobile stations 4 in the cell by wireless. The wireless network control station 1 is normally connected to the base stations 2 by cable.
Next, conventional transmission power control method will be described by using Fig.2. So-called closed loop transmission control performed between the base station and the mobile station will be described.
The setting of the upper limit value and the lower limit value will be described with reference to Figs.3A and 3B. Fig.3A is a graph schematically showing an example of the upper limit value and the lower limit value set for a call. Fig.3B is a graph showing an example of transition of transmission power with respect to time. As shown in Fig.3A, the upper limit value of transmission power occupied by a call is set to be 30% of the maximum power which can be transmitted by the base station, and the lower limit value is set to be 10% of the maximum power which can be transmitted by the base station.
Effects of the upper limit value and the lower limit value exerted on the transmission power of the call will be described by using Fig.3B. The transmission power changes according to before mentioned transmission power control with respect to time. However, when a power value exceeding the upper limit value (30%) should be set according to the transmission power control, the upper limit value functions so as to reduce the transmission power below the upper limit value as shown in the figure.
This reducing control will be described with reference to Figs.4A-4C. In this example, four calls (calls 1 - 4) are connected in which call 1 and call 2 are circuit switching type calls, and call 3 and call 4 are packet switching type calls, and the upper limit value of each call is 5. When transmission power of each call changes while being controlled by the upper limit value as shown in Fig.4A, the total sum of the transmission power of the calls is as shown in Fig.4B.
If the maximum allowable input value of the transmission amplifier is 14, the upper limit value of the transmission power shown in Fig.4B becomes 14 so that the transmission power is to be reduced below 14 if it exceeds 14. Fig.4C shows a graph after the transmission power is reduced. As shown in Fig.4C, parts where transmission power exceeds 14 in Fig.4B becomes flat at 14.
Thus, in a conventional system, high speed transmission power control (Transmitter Power Control : TPC) is performed in up-link and down-link between the base station and the mobile station to change transmission power of each mobile station every moment. More particularly, transmission power of each mobile station is controlled such that each call has a SIR by measuring SIR (Signal/Interference Ratio) of a communication channel.
In the following, the problem will be described in detail with reference to Figs.5-7.
Since TPC continues to function as before even in the above-mentioned situation, the transmission power may exceeds the maximum allowable value according to TPC so that the amplifier may be damaged. In order to solve this problem, an over-input reducing part, which is a limiter for example, is provided before a transmission amplifier such that transmission power larger than a allowable value is not applied to the transmission amplifier in order to protect the transmission amplifier from damaging. In the following, a conventional transmission power control apparatus will be described with reference to Fig.5.
Fig.5 is a block diagram showing only components relating to the present invention in a conventional transmission power control apparatus 600. In this case, the transmission power control apparatus is included in the base station. The transmission power control apparatus 30 includes a plurality of (for example N) baseband signal processing parts 31, transmission power control parts 32 each provided after the baseband signal processing part 31, a baseband signal multiplexing part 33 for multiplexing baseband transmission signals of each call, an over-input control part 34 which is a limiter for example, a power amplifier 35 and an antenna 36.
Next, the above-mentioned power reducing will be described with reference to Figs.6 and 7. Fig.6 shows a schematic graph for a case when transmission power reducing is not performed for transmission power of the base station. Fig.7 shows a schematic graph for a case when the transmission power reducing is performed by the conventional apparatus. In this example, signals are transmitted for calls 1-5, and the maximum allowable transmission power of the base station is 10 on the vertical axis of the graph. Then, it can be recognized that the transmission power exceeds the maximum allowable value at times 2, 3 and 6.
That is, since the conventional apparatus reduces the total transmission power as a whole before the transmission amplifier, the transmission power of each transmission signal is reduced evenly, that is, in a same ratio. Therefore, quality deterioration and the like may be caused to every call. Although decreasing the transmission power evenly for each call may be fair, type of circuit of each call is not considered by this method so that the system becomes inefficient as a whole and can not provide a kind communication service for users.
One known transmission power control apparatus and method is disclosed in a paper titled "Mobile Station - Base Station Compatibility Standard for Dual-Mode Spread Spectrum Systems" TIA/EIA-95-B. This discloses CDMA system in which the maximum output transmission power of a mobile station is controlled so that the mobile station never exceeds the maximum permitted power levels under any circumstances.
Another known method of transmission power control is disclosed in a paper titled "Power Control in UMTS Release, 99" from 3G Mobile Communication Technologies, Conference Publication No. 471. This discloses a CDMA system in which the outer-loop power control sets a target block error rate depending on the particular service being carried. It is disclosed as an example that the target block error rate will usually be higher for a data service than a, voice service.
Another know method of transmission power control is disclosed in US6064659 . This discloses a transmission power control apparatus for wireless communication which prevents transmission power exceeding the maximum allowable power of a power amplifier, in which different subscribers are assigned to different priority groups. When the required transmission power exceeds an allowable maximum transmission power of the power amplifier the power of the calls of the subscriber having the lowest priority is reduced until the required power value is below the maximum transmission power value.
Another known transmission power control apparatus and method is disclosed in US6128506 . This describes a transmission power control system for use in a mobile station in a wireless communication system in which the SIR target of the mobile station is reduced when the total signal power received by a mobile station exceeds a threshold. As a result, when the total received signal power at the mobile station exceeds the threshold the mobile station responds by reducing transmission signal power. This is intended to prevent mutual interference between two mobile stations resulting in a positive feedback loop where each mobile station increases its transmission power in response to interference with the other mobile station.
A further example of the prior art is disclosed in US Patent No 6064659 which relates to a method and system for allocating and limiting transmit power in a transceiver for transmitting to subscriber units in a wireless communications system. In particular, it discloses a system for limiting transmit power when the number of subscribers communicating with a transceiver causes the transceiver to reach or exceed a safe limit.
A yet further example of the prior art is disclosed in US Patent No 6128506 where signal to interference ratio (SIR) is measured and the signal transmission power is changed based on comparisons of measured signals with predetermined threshold values. These changes are made to control signal congestion when transmission power is likely to exceed safe levels.
The above object is achieved by a transmission power control apparatus for a wireless communication apparatus for reducing a power value of a signal input to a power amplifier to the maximum allowable input power value of said power amplifier or below, said transmission power control apparatus comprising:
a power reducing part for reducing transmission power for a plurality of calls;
characterised by a setting part for setting a transmission power upper limit value of said calls according to a circuit type of said call, and that said power reducing part reduces transmission power for said calls to said transmission power upper limit value or below.
The above object is also achieved by a transmission power control apparatus for a wireless communication apparatus for reducing a power value of a signal input to a power amplifier to the maximum allowable input power value of said power amplifier or below, said transmission power control apparatus comprising:
transmission power control parts each for controlling a transmission power of a plurality of calls according to transmission power control information sent from a communication station that is a sending destination of the calls;
characterised by an SIR determining part for determining a control target SIR according to a circuit type of said calls;
a target SIR setting part for sending said control target SIR to said communication station corresponding to said call, wherein said communication station determines said transmission power control information by comparing said control target SIR with an SIR of a received signal,
wherein said SIR determining part monitors occurrence of over-input to said power amplifier, and set another control target SIR when said over-input occurs.
In the transmission power control apparatus, the SIR determining part reduces the first control target SIR by a first predetermines ratio when the over-input to the power amplifier occurs, and the SIR determining part increases the first control target SIR by a second predetermined ratio which is lower then the first predetermined ratio when the over-input to the power amplifier does not occur.
That the over-input occurs even when the control target SIR is set for each call means that the control target SIR is still high. Thus, in such a case, the control target SIR for the calls or the packet switching type is lowered such that communication quality of calls of the circuit switching type is not lowered.
That the call loss occurs even when the control target SIR is set for each call means that power reduction occurs so that communication quality, deteriorates. Thus, in such a case, the control target SIR for the cells of the packet switching type is lowered such that communication quality of cells of the circuit switching type is not lowered.
The above object is also achieved by
a mobile communication system comprising a mobile station and a base station , said system characterised by the mobile station comprising:
a part for comparing a received SIR with a target SIR which is stored in said mobile station, and sending transmission power control information to said base station according to the comparing result;
a part for receiving a control target SIR from said base station, and setting said control target SIR as a new target to be compared with said received SIR;
wherein said base station includes a transmission power
The above object is also achieved by a transmission power control method used for a wireless communication apparatus for reducing a power value of a signal input to a power amplifier to the maximum allowable input power value of said power amplifier or below, said transmission power control method comprising the steps of:
reducing transmission power for a plurality of calls characterised in that said transmission power is reduced to a value or below said value, wherein said value is an upper limit set according to a circuit type of said calls.
reducing the first upper limit value by a first predetermined ratio when the over input to the power amplifier occurs;
controlling a transmission power of a call according to transmission power control information sent from a communication station that is a sending destination of the call;
characterised by determining a control target SIR according to a circuit type of said call; and
sending said control target SIR to said communication station corresponding to said call, wherein said communication station determines said transmission power control information by comparing said control target SIR with an SIR of a received signal, and
wherein said SIR determination monitors occurrence of over input to said power amplifier, and sets another control target SIR when said over-input occurs.
The above object is also achieved by transmission power control apparatus for a wireless communication apparatus for reducing a power value of a signal of calls input to a power amplifier to the maximum allowable input power value of said power amplifier or below, said transmission power control apparatus comprising:
a power reducing part for reducing a power value individually for each group such that a power value of said calls is equal to or below the maximum allowable input power value of said power amplifier;
characterised in that said power reducing part sets an upper limit value of power for each group, and reduces a power value to said upper limit value or below for each group.
In this configuration the calls can be classified into the groups by providing a plurality of baseband signal multiplexing parts each multiplexing a part of transmission signals and by inputting transmission signals of each call into one of the baseband signal multiplexing part.
In this configuration, the change of the upper limit value can be realized by using a limiter in which threshold (upper limit value) can be changed by control from the outside. and by changing the threshold according to the circuit type.
The above object its also achieved by a base station in a wireless communication system, the base station including:
a transmission power control apparatus as set out above.
The above object is also achieved by a transmission power control method used for a wireless communication apparatus for reducing a power value of a signal of calls input to a power amplifier to the maximum allowable input power value of said power amplifier or below, said transmission power control method comprising the steps of:
reducing a power value individually for each group such that a power value of said calls is equal to or below the maximum allowable input power value of said power amplifier,
characterised in that an upper limit value of power is set for each group, and a power value is reduced to said upper limit value or below for each group.
Fig.1 shows an example of a wireless communication system;
Fig.2 shows a block diagram showing a base station and a mobile station for explaining a conventional transmission power control method;
Fig.3A is a graph schematically showing an example of an upper limit value and a lower limit value set for a call;
Fig.3B is a graph showing an example of transition of transmission power with respect to time;
Figs.4A-4C shows graphs for explaining change of transmission signal when receiving transmission power control by a conventional transmission power control apparatus;
Fig.5 is a block diagram of a conventional transmission power control apparatus 600;
Fig.6 shows a schematic graph for a case when transmission power reducing is not performed for transmission power of the base station;
Fig.7 shows a schematic graph for a case when the transmission power reducing is performed by the conventional apparatus;
Fig.8 is a schematic block diagram showing a transmission power control apparatus 100 according to the embodiment 1-1 of the present invention;
Fig.9 is a flowchart of a call establishing process in the transmission power control apparatus 100 of the embodiment 1-1 of the present invention;
Figs.10A-10C are graphs showing an example of change of transmission power with respect to time under transmission power control by the transmission power control apparatus 100 of the embodiment 1-1 of the present invention;
Fig.11 shows a schematic block diagram of a transmission power control apparatus 400 of the embodiment 1-2;
Figs.12 and 13 are flowcharts of call reestablishment process in the transmission power control apparatus 400 of the embodiment 1-2;
Fig.14 show a schematic block diagram of a mobile station 700 of the embodiment 1-3 of the present invention;
Fig.15 is a flowcharts of call reestablishment process in the transmission power control apparatus of the embodiment 1-3;
Figs.16 and 17 are flowcharts of control target SIR reestablishment process in the transmission power control apparatus of the embodiment 1-4;
Fig.18 is a schematic diagram of a transmission power control apparatus 1100 of the embodiment 2-1 of the present invention;
Fig.19 is a schematic block diagram showing a part of the transmission power control apparatus 1200 relating to the embodiment 2-2 of the present invention;
Fig.20 is a flowchart showing the transmission power control method of the transmission power control apparatus 1200 of the embodiment 2-2 of the present invention;
Fig.21 shows a detailed flowchart of a transmission power reducing method in the transmission power control method;
Fig.22 is a graph showing a case in which transmission power reducing process is performed for base station transmission power by the transmission power control apparatus 1200 of the embodiment 2-2.
In the following, first embodiments and second embodiments of the present invention will be described with reference to figures. The first embodiments includes embodiments 1-1 - 1-4 and the second embodiments includes embodiments 2-1 - 2-2.
<First embodiments> (Embodiment 1-1)
First, the transmission power control apparatus of the first embodiment of the present invention will be described by using Figs.8-10C. In this embodiment, probability that over-input to a power amplifier is detected is decreased by providing an upper limit value in transmission power control for transmission signals, and, the upper limit value is provided for each call in a plurality of calls which form a transmission signal according to a circuit type so that communication quality deterioration of calls of circuit switching type is prevented.
Fig.8 is a schematic block diagram showing the transmission power control apparatus 100 according to the first embodiment of the present invention. Fig.9 is a flowchart of a call establishing process in the transmission power control apparatus 100 of the embodiment 1-1 of the present invention. Figs.10A-10C are graphs showing an example of change of transmission power with respect to time under transmission power control by the transmission power control apparatus 100 of the embodiment 1-1 of the present invention. For example, the transmission power control apparatus 100 is included in a base station in a wireless communication system.
The configuration of the transmission power control apparatus 100 will be described with reference to Fig.8. The transmission power control apparatus includes a plurality of (N, for example) baseband.signal processing parts 101, transmission power control parts 102 each provided after the baseband signal processing part 101, a call accept processing part 103 and a call establishing part 104 for establishing and releasing wireless circuits, a baseband signal multiplexing/reducing part 105 for multiplexing/reducing baseband transmission signals of each call, a power amplifier 106, and an antenna 107.
Next, the operation of the transmission power control apparatus 100 of this embodiment will be described. When the transmission power control apparatus 100 receives a call origination request from a mobile station, the call accept processing part 103 obtains the circuit type of the call. Then, the call establishing part 104 determines the upper limit value of the corresponding transmission power control part 102 according to the circuit type. Fig.9 shows the upper limit value determining process according to this embodiment.
Next, the circuit type is determined by the call establishing part 104 in step 202. As mentioned before, the circuit type is classified into the packet switching type and the circuit switching type. The upper limit value A is assigned to a call of the packet switching type, and the upper limit value B is assigned to a call of the circuit switching type in steps 203 and 204.
In this embodiment, the upper limit values A and B are set such that A<B is satisfied. The reason is that the call of the circuit switching type is more susceptible to the effect of power reduction than the packet switching type, and degradation of the communication quality should be avoided for the circuit switching type call. That is, the call of the circuit switching type such as voice communication has strict allowable delay requirement and requires real-time processing, and the call has low tolerance to error. On the other hand, the call of the packet switching type such as data communication has relatively large allowance for delay since the packet switching type has an error correction means such as retransmission request. Thus, this type has relatively large tolerance to error. Thus, the upper limit value for transmission power control for the call of the packet switching type is set to be lower than the value for the circuit switching type, for example, such that A=20%, B=30%.
The transmission power control of this embodiment will be described with reference to Figs.10A-10C. For the sake of easiness of comparison, the example of the transmission power change here is the same as one shown in Fig.4A. In this example, four calls, calls 1-4 are connected, the calls 1 and 2 are the circuit switching type in which the upper limit value is set to be 5, and the calls 3 and 4 are packet switching type in which the upper limit value is set to be 3. When each transmission power of the calls change as shown in Fig.10A while each call receives limitation by the upper limit value, the total sum of the transmission power of the calls becomes as shown in Fig.10B.
If the maximum allowable input value of the transmission amplifier is 14, upper value of the transmission power shown in Fig.10B is 14. When the transmission power value exceeds 14, the value is reduced to 14 by the baseband signal multiplexing/reducing part 105. Fig.10C shows a graph after the total power is reduced. When comparing Fig.10C with Fig.4C, it can be understood that the ratio of transmission power reduction performed by the baseband signal multiplexing/reducing part 105 is decreased, that is, the probability of occurrence of the over-input decreases.
Next, a transmission power control apparatus of the embodiment 1-2 of the present invention will be described with reference to Figs.11-13. In this embodiment, in addition to setting the upper limit value for each call according to the embodiment 1-1, by changing the upper limit value adaptively in communication, it is prevented that the transmission power of the call of the packet switching type is reduced more than necessary, and it is prevented that the whole signals are reduced before the transmission amplifier due to inadequacy of reduction so that the call of the circuit switching type is affected.
Fig.11 show a schematic block diagram of the transmission power control apparatus 400 of the embodiment 1-2. Figs.12 and 13 are flowcharts of call reestablishment process in the transmission power control apparatus 400 of the embodiment 1-2. For example, the transmission power control apparatus 400 is included in a base station in a wireless communication system. The same number is assigned to the same component as the transmission power control apparatus 100 of the embodiment 1-2.
Next, an upper limit reestablishment process in the transmission power control apparatus of this embodiment will be described by using Fig.12.
Although the upper limit of the call of the packet switching type is reestablished triggered by the occurrence of the reducing process in the above embodiment, it is also possible to use occurrence of call loss as the trigger. In the following, a case in which the occurrence of call loss is used as the trigger will be described by using Fig.13. In this case, the occurrence of call loss is monitored by the call accept processing part 103.
Next, a transmission power control method of the embodiment 1-3 of the present invention will be described by using Figs.14 and 15. As mentioned before, in the conventional transmission power control, the received SIR and the target SIR are compared for generating the transmission power control information to the other station. An equivalent process by using the upper limit value in the base station of the embodiments 1-2 and 1-3 can be performed by changing the transmission power control information itself sent from the mobile station by changing the target SIR stored in the mobile station. In this embodiment, a control target SIR is determined according to the circuit type of a call, and the determined control target SIR is sent to the mobile station corresponding to the call so that the mobile station uses the control target SIR for comparison with the received SIR.
Fig.14 show a schematic block diagram of the mobile station 700 of the embodiment 1-3 of the present invention. Fig.15 is a flowcharts of call reestablishment process in the transmission power control apparatus of the embodiment 1-3. The transmission power control apparatus of the embodiment 1-3 has the same configuration as that of the embodiment 1-1. The transmission power control apparatus is included in a base station in a wireless communication system.
Next, the transmission power control method of this embodiment will be described. When the transmission power control apparatus receives a call origination request from the mobile station, the call accept processing part 103 obtains the circuit type of the call. Then, the call establishing part 104 determines the control target SIR according to the circuit type. Fig.15 shows the control target SIR determining process according to this embodiment.
Thus determined control target SIR of the call is sent to the mobile station via the antenna 107 after transmission processing. The control target SIR received by the mobile station is stored in the control target SIR storing part 705 by the call control circuit 704. After that, the control target SIR is used as the target SIR for comparing processing in the comparing circuit 706.
Next, a transmission power control apparatus of the embodiment 1-4 of the present invention will be described with reference to Figs.16-17. In this embodiment, in addition to setting the control target SIR for each call according to the embodiment 1-3, by changing the control target SIR adaptively in communication, it is prevented that the transmission power of the call of the packet switching type is reduced more than necessary, and it is prevented that the whole signals are reduced before the transmission amplifier due to inadequacy of reduction so that the call of the circuit switching type is affected.
Figs.16 and 17 are flowcharts of control target SIR reestablishment process in the transmission power control apparatus of the embodiment 1-4. The transmission power control apparatus of this embodiment has the same configuration as that of the embodiment 1-2, and the mobile station of this embodiment has the same configuration as that of the embodiment 1-3. For example, the transmission power control apparatus is included in a base station in a wireless communication system.
First, the control target SIR reestablishment process in the transmission power control apparatus of this embodiment will be described by using Fig.16 which shows a case in which the occurrence of reduction process is used as a trigger.
Next, it is judged whether the reduction process does not occur for a predetermined period by comparing the value A with a predetermined value N in step 905. When the value A is equal to or more than N, calls of the packet switching type are selected in step 906, and the control target SIR for the calls is increased by Y. After that, the counter A is cleared again in step 901 and the monitoring of the occurrence of the reduction process continues in step 902.
Next, a process for a case where call loss is used as a trigger will be described by using
A transmission power control apparatus 1100 and the transmission power reduction method of the embodiment 2-1 of the present invention will be described with reference to Fig.18. Fig.18 is a schematic diagram showing a part relating to the present invention in the transmission power control apparatus 1100 of the embodiment 2-1 of the present invention. The transmission power control apparatus 1100 is characterized by a plurality of baseband signal multiplexing parts. The transmission power control apparatus 1100 is included in a base station in a wireless communication system for example.
Next, a transmission power control apparatus 1200 and a transmission power reducing method of the embodiment 2-2 of the present invention will be described by using Figs.19-22. Fig.19 is a schematic block diagram showing a part of the transmission power control apparatus 1200 relating to the embodiment 2-2 of the present invention. Fig.20 is a flowchart showing the transmission power control method of the transmission power control apparatus 1200 of the embodiment 2-2 of the present invention. Fig.21 shows a detailed flowchart of a transmission power reducing method in the transmission power control method. Fig.22 is a graph showing a case in which transmission power reducing process is performed for base station transmission power by the transmission power control apparatus 1200 of this embodiment.
The transmission power control apparatus 1200 of this embodiment reduces the transmission power by assigning weight to amplitude of transmission signal of each call. The transmission power control apparatus is included in a base station in a wireless communication system for example.
First, the configuration of the transmission power control apparatus 1200 will be described by using Fig.19. The same number is assigned to the same component of the transmission power control apparatus 1100 of the embodiment 2-1. The transmission power control apparatus 1200 includes a plurality of (for example N) baseband signal processing parts 1101, transmission power control parts 1102 each provided after the baseband signal processing part 1101, a power reducing part 1201 for reducing transmission power of the transmission signal, a priority information control part 1206, a priority information storing part 1207 which is a memory for example, a power amplifier 1108 and an antenna 1109. The power reducing part 1201 includes a baseband signal storing part 1202 including at least a memory, a power reducing control part 1203 for controlling signal processing in the power reducing part 1201, a baseband signal multiplexing part 1204 for multiplexing input signals, an over-input detection part 1205, and a weight processing part 1208 for performing weight processing on the basis of priorities set for transmission signal of each call.
Next, a transmission power reducing method of this embodiment will be described by using Fig.20.
Next, a determining algorithm (corresponding to step 1304 and step 1305 in Fig.20) of the weight coefficients used in the power reducing control part 1203 will be described by using Fig.21. According to this algorithm, weight coefficients are determined such that higher priority is assigned to a call for which degradation of communication quality should be avoided and transmission power is reduced from a call in order of increasing priority when the transmission power should be reduced (when over-input occurs).
When over-input is detected by the over-input detection part 1205 and this detection is notified to the power reducing control part 1203, tne reducing algorithm starts in the power reducing control part 1203.
Next, data in the table generated in step 1401 is rearranged by using priority as a key in step 1402, a priority of a call (which is not limited to one call) having the lowest priority at this time is determined as a priority (which will be called "priority Pri" in the following) which indicates a subject to bye decreased.
An example of a process result of the transmission power reducing method of this embodiment is shown in Fig.22. Fig.22 is a graph schematically showing a case in which transmission power reduction process is performed by the transmission power control apparatus 1200. The condition of this example is the same as that of Fig.6, in which signals are transmitted for calls 1-5, and it is assumed that the maximum allowable transmission power value of the base station is 10 on the vertical axis of the graph, and the transmission power exceeds at times 2, 3 and 6.
In addition, in Fig.22, priority of a call 1 is the highest, and the priority of call 5 is the lowest, and priorities of calls 2-4 are the same.
In this condition, as shown in Fig.22, at the times of 2 and 3, by reducing only the transmission power of the call 5, whole transmission power falls within 10. At the time of 6, the whole transmission power does not fall within 10 only by reducing the transmission power of call 5. In this case, the transmission power of call 5 is set to the minimum value, and, in addition, the transmission powers of calls 2-4 having low priority are reduced equally. In any time, the transmission power of the call 1 which has the highest priority is constant in which the transmission power of the call 1 is unaffected by the transmission power reduction.
That is, communication quality is kept.
The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the invention as defined by the appended claims.
A transmission power control apparatus (102) for a wireless communication apparatus for reducing a power value of a signal input to a power amplifier (106) to the maximum allowable input power value of said power amplifier or below, said transmission power control apparatus comprising:
a power reducing part for reducing transmission power for each call in a plurality of calls;
characterised by a setting part for setting a transmission power upper limit value for each of said calls according to a circuit type of said calls, and that said power reducing part reduces transmission power for each of said calls to said transmission power upper limit value or below.
The transmission power control apparatus as claimed in claim 1, wherein said setting part sets said transmission power upper limit value according to a degree of delay which can be allowed for said circuit type.
The transmission power control apparatus as claimed in claim 1, wherein said setting part sets a first upper limit value for a call of a packet switching type or a second upper limit value for a call of a circuit switching type.
The transmission power control apparatus as claimed in claim 3, wherein said first upper limit value is smaller than said second upper limit value.
The transmission power control apparatus as claimed in claim 3, wherein said setting part monitors occurrence of over-input to said power amplifier, and sets another transmission power upper limit value when said over-input occurs.
The transmission power control apparatus as claimed in claim 5, wherein, said setting part reduces said first upper limit value by a first predetermined ratio when said over-input to said power amplifier occurs, and said setting part increases said first upper limit value by a second predetermined ratio which is lower than said first predetermined ratio when said over-input to said power amplifier does not occur.
The transmission power control apparatus as claimed in claim 1, wherein said setting part monitors occurrence of over-input to said power amplifier, and sets another transmission power upper limit value when said over-input occurs.
The transmission power control apparatus as claimed in claim 1, wherein said setting part monitors occurrence of call loss, and sets another transmission power upper limit value when said call loss occurs.
transmission power control parts each for controlling a transmission power of a plurality of calls according to transmission power control information sent from a communication station that is a sending destination of the calls; characterised by
an SIR determining part for determining a control target SIR according to a circuit type of said calls;
wherein said SIR determining part monitors occurrence of over-input to said power amplifier, and sets another control target SIR when said over-input occurs.
The transmission power control apparatus as claimed in claim 9, wherein said SIR determining part sets said control target SIR according to a degree of delay which can be allowed for said circuit type.
The transmission power control apparatus as claimed in claim 9, wherein said SIR determining part sets a first control target SIR for a call of a packet switching type or a second control target SIR for a call of a circuit switching type.
The transmission power control apparatus as claimed in claim 11, wherein said first control target SIR is smaller than said second control target SIR.
The transmission power control apparatus as claimed in claim 11, wherein, said SIR determining part reduces said first control target SIR by a first predetermined ratio when said over-input to said power amplifier occurs, and said SIR determining part increases said first control target SIR by a second predetermined ratio which is lower than said first predetermined ratio when said over-input to said power amplifier does not occur.
The transmission power control apparatus as claimed in claim 9, wherein said SIR determining part monitors occurrence of call loss, and sets another control target SIR when said call loss occurs.
The transmission power control apparatus as claimed in claim 1, wherein said transmission power control apparatus is provided in a base station (2) of a wireless communication system.
The transmission power control apparatus as claimed in claim 9, wherein said transmission power control apparatus is provided in a base station (2) of a wireless communication system.
A mobile communication system comprising a mobile station (4) and a base station (2), said system characterised by the mobile station comprising:
a part (706) for comparing a received SIR with a target SIR which is stored in said mobile station, and sending transmission power control information to said base station according to the comparing result;
a part (703) for receiving a control target SIR from said base station, and setting said control target SIR as a new target SIR to be compared with said received SIR;
wherein said base station includes a transmission power control apparatus as claimed in claim 9.
A transmission power control method used for a wireless communication apparatus for reducing a power value of a signal input to a power amplifier (106) to the maximum allowable input power value of said power amplifier or below, said transmission power control method comprising the steps of:
reducing transmission power for a plurality of calls characterised in that said transmission power is reduced to a value or below said value, wherein said value is an upper limit set (S203, 204) according to a circuit type of said calls.
The transmission power control method as claimed in claim 18, wherein said transmission power upper limit value is set according to a degree of delay which can be allowed for said circuit type.
The transmission power control method as claimed in claim 18, wherein a first upper limit value for a call of a packet switching type or a second upper limit value for a call of a circuit switching type is set as said transmission power upper limit value.
The transmission power control method as claimed in claim 20, wherein said first upper limit value is smaller than said second upper limit value.
The transmission power control method as claimed in claim 20, wherein another transmission power upper limit value is set when said over-input to said power amplifier occurs.
The transmission power control method as claimed in claim 22, comprising the steps of:
reducing said first upper limit value by a first predetermined ratio when said over-input to said power amplifier occurs (S504);
increasing said first upper limit value by a second predetermined ratio which is lower than said first predetermined ratio when said over-input to said power amplifier does not occur (S508).
The transmission power control method as claimed in claim 18, wherein another transmission power upper limit value is set when over-input to said power amplifier occurs.
The transmission power control method as claimed in claim 18, wherein another transmission power upper limit value is set when call loss occurs.
controlling a transmission power of a plurality of calls according to transmission power control information sent from communication stations that are sending destinations of the calls;
characterised by determining a control target SIR according to a circuit type of said call (S803, S804); and
sending said control target SIR to said communication stations corresponding to said calls, wherein said communication stations determines said transmission power control information by comparing said control target SIR with an SIR of a received signal, and
The transmission power control method as claimed in claim 26, wherein said control target SIR is set according to a degree of delay which can be allowed for said circuit type.
The transmission power control method as claimed in claim 26, wherein a first control target SIR for a call of a packet switching type or a second control target SIR for a call of a circuit switching type is set.
The transmission power control method as claimed in claim 28, wherein said first control target SIR is smaller than said second control target SIR.
The transmission power control method as claimed in claim 28, wherein another control target SIR is set when over-input to said power amplifier occurs.
The transmission power control method as claimed in claim 30, comprising the steps of:
reducing said first control target SIR by a first predetermined ratio when said over-input to said power amplifier occurs (S904);
increasing said first control target SIR by a second predetermined ratio which is lower than said first predetermined ratio when said over-input to said power amplifier does not occur (S907).
The transmission power control method as claimed in claim 27, wherein another control target SIR is set when over-input to said power amplifier occurs.
The transmission power control method as claimed in claim 26, wherein another control target SIR is set when call loss occurs (S1004).
A transmission power control apparatus (102) for a wireless communication apparatus for reducing a power value of a signal of calls input to a power amplifier (106) to the maximum allowable input power value of said power amplifier or below, said transmission power control apparatus comprising:
The transmission power control apparatus as claimed in claim 34, wherein said classifying part classifies said calls according to degree of delay which is allowed by a circuit type of each call.
The transmission power control apparatus as claimed in claim 34, wherein said classifying part classifies said calls into a group of a circuit switching type and a group of a packet switching type.
The transmission power control apparatus as claimed in claim 36, wherein said upper limit value for a group of said packet switching type is smaller than said upper limit value for a group of said circuit switching type.
The transmission power control apparatus as claimed in claim 36, wherein said power reducing part reduces only a power value of a group of said packet switching type.
The transmission power control apparatus as claimed in claim 34, wherein the number of said plurality of groups and said upper limit value for each group are changed according to types of said calls.
The transmission power control apparatus as claimed in claim 34, wherein said classifying part assigns priority for each call according to circuit characteristics of said each call, and said power reducing part reduces a power value of a call according to said priority.
The transmission power control apparatus as claimed in claim 40, wherein said classifying part assigns said priority such that the larger a degree of delay which is allowed by said call is, the lower said priority is, and,
The transmission power control apparatus as claimed in claim 41, wherein said power reducing part does not reduce a power value of a call which has priority within predetermined levels from the highest priority.
A base station (2) in a wireless communication system, said base station comprising:
a transmission power control apparatus as claimed in claim 34.
A transmission power control method used for a wireless communication apparatus for reducing a power value of a signal of calls input to a power amplifier (106) to the maximum allowable input power value of said power amplifier or below, said transmission power control method comprising the steps of:
The transmission power control method as claimed in claim 44, wherein said calls are classified according to degree of delay which is allowed by a circuit type of each call.
The transmission power control method as claimed in claim 45, wherein said calls are classified into a group of a circuit switching type and a group of a packet switching type.
The transmission power control method as claimed in claim 46, wherein said upper limit value for a group of said packet switching type is smaller than said upper limit value for a group of said circuit switching type.
The transmission power control method as claimed in claim 46, wherein only a power value of a group of said packet switching type is reduced.
The transmission power control method as claimed in claim 44, wherein the number of said plurality of groups and said upper limit value for each group are changed according to types of said calls.
The transmission power control method as claimed in claim 44, comprising the steps of:
The transmission power control method as claimed in claim 50, comprising the steps of:
reducing each power value of a part of calls in ascending order of said priority such that a power value of calls input to said power amplifier is equal to or below the maximum allowable input power value of said power amplifier.
The transmission power control method as claimed in claim 51, wherein a power value of a call which has priority within predetermined levels from the highest priority is not reduced.
assigning said priority such that the larger a degree of delay which can be allowed by allowed by said call, the lower said priority is;
EP20020250327 2001-01-18 2002-01-17 Transmission power control apparatus, transmission power control method, and mobile station Expired - Fee Related EP1239602B1 (en)
JP2001010764A JP3717787B2 (en) 2001-01-18 2001-01-18 Transmission power control apparatus and method transmit power compression
JP2001010765A JP3717788B2 (en) 2001-01-18 2001-01-18 Transmission power control apparatus and its transmit power control method, and mobile station apparatus
JP2001010765 2001-01-18
JP2001010764 2001-01-18
EP1239602A2 true EP1239602A2 (en) 2002-09-11
EP1239602A3 true EP1239602A3 (en) 2004-04-28
EP1239602B1 true EP1239602B1 (en) 2010-12-29
ID=26607918
EP20020250327 Expired - Fee Related EP1239602B1 (en) 2001-01-18 2002-01-17 Transmission power control apparatus, transmission power control method, and mobile station
US (1) US7167718B2 (en)
EP (1) EP1239602B1 (en)
CN (1) CN100459472C (en)
DE (1) DE60238732D1 (en)
KR101593580B1 (en) * 2009-01-07 2016-02-15 삼성전자주식회사 A transmission power control method and apparatus
JP5341212B2 (en) 2009-02-18 2013-11-13 テレフオンアクチーボラゲット エル エム エリクソン（パブル） Method and arrangement in a communication system
ES2610785T3 (en) 2012-08-17 2017-05-03 Huawei Device Co., Ltd. Method for reducing energy consumption in the handset and handset
CN100459472C (en) 2009-02-04 grant
US20020094835A1 (en) 2002-07-18 application
DE60238732D1 (en) 2011-02-10 grant
CN1366391A (en) 2002-08-28 application
EP1239602A3 (en) 2004-04-28 application
US7167718B2 (en) 2007-01-23 grant
EP1239602A2 (en) 2002-09-11 application
US20050239413A1 (en) 2005-10-27 Load control in shared medium many-to-one communication systems
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