Be used for the Poewr control method under the continuity grouping connection status
Technical field
The present invention relates to moving communicating field, relate in particular to a kind of Poewr control method that is used under the continuity grouping connection status.
Background technology
Along with the professional development of IP Multimedia System (IMS), can find that the IP based network Telecom Service Development has been current trend of the times.This type business have open flexibly, relate to characteristics such as network element is few, the construction cycle is short, renewal speed is fast, more can adapt to the development of Network undoubtedly.The current instant messaging that becomes more and more popular (IM) has been simplified to communication service the structure of a kind of " client-server " simultaneously; Such business has a basic demand; Require communication terminal to be in line states exactly always, therefore need network system can support the function that IP is always online.
High-speed downlink packet inserts (HSDPA) technology and has lighted the hope that the user continues to be connected with High Speed Uplink Packet access (HSUPA) technology; Under this scene; The user can keep connection status in long time; Only carry out the transmission of data once in a while, avoided frequent connection termination, rebulid and intrinsic expense and the time delay brought thus.
In existing mobile communications system; For fear of interrupting continually between user and the base station and being connected; Even data channel just sends data in several activation cycles once in a while; Up (UL) Dedicated Physical Control Channel (DPCCH) also keep to send the state of data always, has wasted the resource of system to a certain extent, has increased interference to other users, has reduced the capacity of system.Third generation partner program (3GPP) the R7 stage has proposed a solution---and continuity divides into groups to connect (Continuous Packet Connectivity; Be called for short CPC) technology; Be used for when data channel does not have transfer of data keeping being connected between HSUPA/HSDPA user and the base station, reduce other users' interference simultaneously and frequently interrupt, connect the expense of bringing.
Referring to Fig. 1, it is the parameter sketch map of UL DPCCH under the CPC state in the prior art.Under the CPC state, UL DPCCH sends no longer continuously, but sends discontinuously with certain cycle, is operated in activation (active)/non-activation (inactive) pattern.Both do not strengthen dedicated channel (E-DCH) transmission, also do not have High-Speed Dedicated Physical Control Channel (HS-DPCCH) transmission in; Subscriber equipment (UE; User Equipment; 3GPP calls for portable terminal) will stop the DPCCH emission automatically, and use a predefined DPCCH bursts of activities (burst).In case E-DCH and HS-DPCCH begin emission, recover normal DPCCH emission immediately.In order between non-active period, to keep necessary uplink synchronous, predefined DPCCH bursts of activities must keep certain transmission cycle.Up discontinuous transmission (being called for short UL DTX) uses two kinds of discontinuous DPCCH to send cycle: UE_DTX_cycle_2 and UE_DTX_cycle_1, and the former is the latter's a integral multiple.In order further to reduce uplink interference, different users' power is presented even distribution on time domain, can be specific time migration of each UE configuration.
Fig. 1 has provided the transmit cycle of UL DPCCH under the channel E-DCH state of activation, the transmit cycle that can find out DPCCH by fixing burst, leading (Preamble), after lead (Postamble) and other channels (for example E-DCH) activation cycle form.Though the resource of system has been practiced thrift in the discontinuous transmission of UL DPCCH under the CPC state; Reduced other users' interference and increased the capacity of system; But also brought a problem simultaneously, how that carries out the problem of power control (TPC) exactly under the CPC state.
Power control techniques is the key technology of WCDMA (WCDMA) GSM, the WCDMA system be one from the interference system, all subscriber equipmenies (be called for short UE) all take same band and frequency; If all UE launch with identical power in the sub-district; Because each UE is different with the distance and the path of base station (being called for short Node B), signal arrives Node B and just has different attenuations, thereby causes from the nearer UE of Node B; The signal that Node B receives is strong; From Node B UE far away, a little less than the signal that Node B receives, will cause the intensity of the received signal of Node B to differ greatly like this; Weak signal far away maybe not can be come out by despreading after arriving Node B; Cause weak signal " to flood " in strong signal, and then the communication of blocking most of zone, sub-district, thereby the problem that in the WCDMA system, is called as " near-far interference " produced.The purpose of power control overcomes " far and near effectiveness " exactly, guarantees that each user institute transmitting power arrives the base station and keeps minimum, can meet minimum communicating requirement, avoids again simultaneously other subscriber signals are produced unnecessary interference, makes the power system capacity maximization.
In the WCDMA system, power control can be divided into uplink power control by direction and descending power is controlled two types; Whether participate in being divided into again open Loop Power control and closed power control two big classes simultaneously by UE and Node B.Closed-loop power control is meant the process that feedback information that transmitting terminal is sent here according to receiving terminal is controlled transmitting power; And open loop power control does not need the feedback of receiving terminal, and the information that transmitting terminal measures according to self is controlled transmitting power.The uplink closed loop technology is a kind of power control techniques the most frequently used in the HSPA system, and the physical layer between Node B and UE is carried out, and the purpose of up inner loop power control is that the bit energy that makes the base station receive each UE signal equates.Referring to Fig. 2, it is the sketch map of up inner loop power control in the prior art.At first; The signal-to-jamming ratio (SIR) of the upward signal that Node B measurement receives; And compare with the target SIR (target SIR is handed down to Node B by RNC (radio network controller)) that is provided with, if measure SIR less than target SIR, the TPC sign notice UE of Node B in descending physical channel fractional dedicated physical channel (F-DPCH) improves transmitting power; Otherwise notice UE reduces transmitting power.
The TPC mode that at present the CPC state is commonly used down is that the fixedly burst according to UL DPCCH carries out power control; The signal-to-jamming ratio (SIR) that promptly only receives in the location estimation of fixing bursts of activities burst; And compare it with the target SIR value; If the SIR that records is higher than target SIR, Node B just orders UE to reduce power; If the SIR that records is lower than target SIR, Node B just orders UE to raise power.Other positions (as leading, after lead the activation cycle with other channels) do not carry out power control.This kind method, less at the burst of UL DPCCH period ratio, and channel circumstance can meet the demands when changing more fully.But at the burst of UL DPCCH period ratio big (the regulation UE_DTX_cycle2 according to agreement possibly reach 160 sub-frame); And channel circumstance changes than (for example under the fading channel condition) under the situation faster; Just utilization is fixedly carried out power control in the position of burst; Can cause the UE transmitting power can't follow the variation of channel circumstance, cause transmitting power excessive or too small, greatly reduce capability of communication system.
Summary of the invention
The transmitting power of subscriber equipment the object of the present invention is to provide a kind of Poewr control method that is used under the continuity grouping connection status, so that can be followed the variation of channel circumstance better and changed.
For realizing above-mentioned purpose, the Poewr control method that is used under the continuity grouping connection status provided by the invention comprises:
Step 1, in base station end, according to the upward signal that receives, calculate the SIR estimated value of current time slots (slot);
Step 2, judge a last slot the SIR estimated value whether greater than preset thresholding (this thresholding is designated as Thr); If SIR<=Thr forwards step 3 to, otherwise then forwards step 4 to; Skips steps two when having the judged result of a last slot, directly get into step 3;
Step 3, be 1 (representing that current slot is in the DTX state), and SIR estimated value and the thresholding Thr of current slot compared the record comparative result the DTX mark position of current slot;
Step 4, the SIR estimated value of the SIR estimated value of current slot and a last slot done on average obtain the SIR estimated mean value, and SIR estimated mean value and thresholding Thr are compared.If SIR estimated mean value>thresholding, then the DTX mark position with current slot was 0 (representing that current slot is not in the DTX state), otherwise then forwarded step 3 to;
Step 5, confirm according to the DTX flag bit of each current slot whether the SIR estimated value of UL DPCCH current time slots is used for doing uplink closed-loop power control.
Wherein, when DTX=1, do not do uplink closed-loop power control; When DTX=0, do uplink closed-loop power control.
Wherein, the DTX flag bit of current time slots equals at 1 o'clock, and the SIR estimated value of current time slots is not used for doing uplink closed-loop power control; When DTX=0, the SIR estimated value of current time slots is used for doing uplink closed-loop power control.
Wherein, When doing uplink closed-loop power control in the said step 5, if when the SIR estimated value of current time slots is lower than preset target SIR, the base station commands subscriber equipment improves transmitting power; When if the SIR estimated value of current time slots is higher than target SIR, the base station commands subscriber equipment reduces transmitting power.
According to method provided by the invention, DTX flag bit state initial value is set to 1, representes that current slot does not do uplink closed-loop power control.
According to method provided by the invention, said thresholding Thr value is perhaps tested empirical data according to simulation study and is confirmed.
According to method provided by the invention, this method is applied in the uplink closed loop under the CPC pattern in the WCDMA system.
Beneficial effect of the present invention: the Poewr control method that is used under the continuity grouping connection status provided by the invention; It utilizes preset thresholding, confirms whether special physical controlling channel of upward is in the DTX state, when it is the DTX state; Uplink closed-loop power control is closed; Otherwise, utilize the signal-to-jamming ratio information of special physical controlling channel of upward to carry out uplink closed-loop power control, can so that the transmitting power of subscriber equipment follow the variation of channel circumstance better and change; Even it is bigger at the burst of special physical controlling channel of upward period ratio; And channel circumstance changes than also carrying out power control well under the situation faster, makes its average power reach minimum, has improved capability of communication system greatly.
In order further to understand characteristic of the present invention and technology contents, see also following about detailed description of the present invention and accompanying drawing, yet accompanying drawing only provide reference and the explanation usefulness, be not to be used for the present invention is limited.
Description of drawings
Below in conjunction with accompanying drawing, describe in detail through specific embodiments of the invention, will make technical scheme of the present invention and other beneficial effect obvious.
In the accompanying drawing,
Fig. 1 is the parameter sketch map of UL DPCCH under the CPC state in the prior art;
Fig. 2 is the sketch map of up inner loop power control in the prior art;
Fig. 3 is used for the flow chart of Poewr control method one preferred embodiment under the continuity grouping connection status for the present invention;
Fig. 4 is transmitting power and the average power sketch map of existing Poewr control method UE;
Fig. 5 is transmitting power and the average power sketch map of Poewr control method UE of the present invention;
Fig. 6 is the comparison diagram of existing Poewr control method and Poewr control method cell throughout of the present invention.
Embodiment
See also Fig. 3, it is the flow chart that the present invention is used for a preferred embodiment of the Poewr control method under the continuity grouping connection status, may further comprise the steps:
Step 301: the SIR estimated value of calculating current slot;
Step 302: otherwise whether the SIR estimated value of judging a last slot if SIR<=Thr forward step 304, then forwards step 303 greater than thresholding Thr, when not having the judged result of a last slot, skips this step 302, directly gets into step 304;
Step 304: with the DTX mark position of current slot is 1, and SIR estimated value and the thresholding Thr of current slot compared, the record comparative result;
Step 303: the SIR estimated value of the SIR estimated value of current slot and a last slot averaged obtain the SIR estimated mean value, and SIR estimated mean value and thresholding are compared, if SIR estimated mean value mean value<=thresholding then forwards step 304 to;
Step 305: in the step 303, if SIR estimated mean value mean value>thresholding, then the DTX mark position with current slot is 0;
Step 306: whether the SIR estimated information of judging the current slot of UL DPCCH according to the DTX flag bit is used to do uplink closed-loop power control.During like DTX=1, do not do uplink closed-loop power control; During like DTX=0, then do uplink closed-loop power control.
When doing uplink closed-loop power control; When if the signal-to-jamming ratio of current data signal is lower than target sir; The base station commands subscriber equipment improves transmitting power, if when the signal-to-jamming ratio of current data signal is higher than target sir, the base station commands subscriber equipment reduces transmitting power; Will cause the intensity of all received signals of base station all the same like this; Thereby avoided the situation that weak signal " is flooded " in strong signal to take place to guarantee that each subscriber equipment institute transmitting power reaches the base station and keeps minimum, can meet minimum communicating requirement, avoided again simultaneously other subscriber signals are produced unnecessary interference; Make the power system capacity maximization, said target sir is set according to actual needs.
The invention provides under a kind of CPC condition whether effectively detection method of TPC order; Under the CPC condition, utilize the information of the UL DPCCH that Preamble, Postamble and other channels launch in activation cycle to do uplink closed loop.Utilize preset thresholding, confirm whether UL DPCCH is in the DTX state, and when it was the DTX state, uplink closed-loop power control was closed; Otherwise, utilize the SIR information of UL DPCCH to carry out uplink closed-loop power control.Poewr control method of the present invention is applicable in the WCDMA system, the uplink closed loop under the continuity grouping connection mode.
The still UL DPCCH that UL DPCCH sends on the position of Preamble, Postamble and other channels activation cycles in essence; Only position such as Preamble and Postamble does not have corresponding HS-DPCCH and E-DCH channel; Therefore we can utilize leading (Preamble), after lead (Postamble) and other channels UL DPCCH of emission in activation cycle information do uplink closed loop; Can make the UE transmitting power follow the variation of channel circumstance better like this, improve capability of communication system.
According to method provided by the invention; Can detect simply and easily leading (Preamble), after lead the DPCCH information in the activation cycle of (Postamble) and other channels; And the signal-to-jamming ratio estimated value of special physical controlling channel of upward is used for uplink closed loop at this moment; Make the transmitting power of subscriber equipment closely follow the variation of channel circumstance; Reduce the multiple access interference, overcome the influence of near-far interference and decline, thereby guaranteed the quality of uplink downlink, improved the capacity of system.For example: the transmitting power that under the prerequisite that guarantees internet services quality (Qosde), reduces certain subscriber equipment; With the quality of reception that can not influence its up-downgoing data; But the result has reduced system interference, and the uplink downlink quality of other subscriber equipment will be improved.
See also Fig. 4 and Fig. 5, it is respectively transmitting power and the average power sketch map subscriber equipment that uses the UE of existing Poewr control method and Poewr control method of the present invention in the actual test environment.Can find out and use Poewr control method of the present invention; The transmitting power fluctuation ratio of subscriber equipment is less; And also little about 1~2dB when using existing Poewr control method of average transmit power; Can more effectively overcome " near-far interference " like this, reduce interference, improve the capacity of system the sub-district.
See also Fig. 6; It is the contrast of the cell throughout of existing Poewr control method and Poewr control method of the present invention; Therefrom can find out and use Poewr control method of the present invention, can control inter-user interference better, improve the utilance of power, more effectively utilize Radio Resource, thereby the throughput that improves the sub-district (uses Poewr control method of the present invention under the situation of same subscriber number; Cell throughout on average improves 10%), and then the user capacity and the speech quality of raising whole system.
In sum, the Poewr control method that is used under the continuity grouping connection status provided by the invention, it utilizes preset thresholding; Confirm whether special physical controlling channel of upward is in the DTX state; When it was the DTX state, uplink closed-loop power control was closed, otherwise; Utilize the signal-to-jamming ratio information of special physical controlling channel of upward to carry out uplink closed-loop power control; Can be so that the transmitting power of subscriber equipment be followed the variation of channel circumstance better and is changed, even bigger at the burst of special physical controlling channel of upward period ratio, and channel circumstance changes than also carrying out power control well under the situation faster; Make its average power reach minimum, improved capability of communication system greatly.
The above for the person of ordinary skill of the art, can make other various corresponding changes and distortion according to technical scheme of the present invention and technical conceive, and all these changes and distortion all should belong to the protection range of claim of the present invention.