A thesis submitted in part fulfillment of the degree of master of engineering by research at the faculty of engineering elniversity of technology, sydney. It gives an overview from a control perspective of achievements in the area to date with some illuminating examples and pointers to interesting open issues. Umts power control open loop power control is the ability of the ue transmitter to sets its output power to a specific value. The umts protocol stack is an enormous project with specifications involving thousands of pages. Power control in umts power control in umts can be widely classified as two types. Currently, wcdma networks are deployed in umts band of around 2 ghz in europe and asia, including japan and america korea. Also, know about frequency bands used in 3g networks. Power control in umts release 99 request pdf researchgate. A power control algorithm for 3g wcdma system citeseerx. Control theory aspects of power control in umts sciencedirect.
Eng abstract radio resource management rrm is an essential topic when 3g wcdma networks are being developed. During this open loop control, it is assumed that both forward link from bs to ms and reverse link from ms to bs are correlated. Deals with power control, channel assignment and handoff decisions. Request pdf power control in umts release 99 the cdma technology used in umts relies on accurate power control techniques, not only for maximising. Hanus, admission control techniques for umts system the voice activity factor of the j th session. The handover and power control algorithms have been developed and implemented in the framework of a system level. The universal mobile telecommunications system umts, based on the gsm standards, is a mobile cellular system of third generation that is maintained by 3gpp 3rd generation partnership project. Comprehesive coverage of umts 3g news, licensing, business developments, 3g wcdma telecommunication technology, multi media mobile phones and future communications. Common pilot channel power control for umts cellular. Wideband code division multiple access wcdma is the physical layer used for universal terrestrial radio access utra fdd mode. Study these interview mcq questions and answers on 3g umts wcdma network architecture and interfaces. The chapter structure has been reworked for improved usability for readers, as well as including many new features and updates. The wcdma technology provides the umts system some of the new functionalities on the air interface.
Terminals work as an air interface counter part for nodeb and have many different types of identities. In the closed loop power control, feedback is used for adjusting the transmit power level. In this paper we present a soft handover algorithm for wide band cdma based e umts networks and the associated power control algorithm. The importance of diversity is analyzed together with fast power. Spreading and scrambling transport channel combining soft handover compressed mode power control. Usim umts subscriber identity module is a smart card that holds the subscriber identity, subscribed services, authentication and encryption keys utran node b equivalent to bts in gsmgprs performs the air interface processing channel coding, rate adaptation, spreading, synchronization, power control. With algorithm 2, the inner loop power control is performed every five timeslots, that is, the frequency is lower to perform inner loop power control in algorithm 2. An energy efficient semistatic power control and link adaptation scheme in umts hsdpa yi huang, jie xu and ling qiu abstract high speed downlink packet access hsdpa has been successfully applied in commercial systems and improves user experience significantly. Moreover, it is capable of tracking rapid changes in fast fading channels, where conventional umts power control algorithms fail to handle. For details of lte specific power control, you have to refer to ts 36.
Amr codec in umts 379 from radio quality measurements and from traffic volume measurements. The migration to umts is proposed as a simple way to reduce exposure to electromagnetic waves of the mobile telephony user. Queuebased power control in umts systems luigi chisci, lorenzo mucchi and tommaso pecorella abstractin modern cellular communication systems, power control plays a fundamental role for ef. Power control in wcdma is a closedloop pc which is a combination of outer and. However to ensure the competitiveness of umts for the next decade and beyond, concepts for umts long term evolution lte have been first time introduced in 3gpp release 8. Transport formats in umts radio network controllers software implementation degree programme communications engineering laboratory communications laboratory s72 supervisor docent timo o. Umts technology explained umts technology explained, ppt file. In such systems, in fact, many users transmit over the same radio channel using the same frequency band and time slots so that the. Power control and if you want to have some handson experience of these, i would recommand you to try some test items on 36. Power control ilpc and the outer loop power control olpc.
If the maximum output power is too high, the device may interfere with other channels or other systems. In conclusion, power control is extremely important in umts. Whereas power saving on cpich may not be a crucial aspect to the power controlled voice traffic, it is of great significance to data traffic. Pdf the outer loop power control olpc in wcdma systems allows to achieve a defined quality of service qos for every link. The design contains a lot of flexibility to allow power control at different levels. This completely revised and updated edition of the highly successful umts signaling provides a deep insight into all aspects of umts signalling. After getting strong concept of umts radio architecture and procedures, we worked on different rrm techniques and in the end we analyze two power control. It handles power control, modulation and measurements.
The device is configured as master unit of zpc line remote io system. The relationship between fast power control and diversity. Due to this fact umts deploys a strict power control, composed by the inner loop. Open loop power control vs closed loop power control. It is used for setting initial uplink and downlink transmission powers when a ue is accessing the network. The open loop power control tolerance is 9 db normal conditions or 12 db extreme conditions. Ue rnc request to modify the amr mode in dl amr encoded speech data in ul ongoing call amr encoded speech data in dl with new amr mode ongoing call request to modify the amr mode. Dec 09, 2007 in conclusion, power control is extremely important in umts. Outerloop power control in a live umts network tu wien.
Moreover, reducing the cpich power enables additional power saving on some of the other common control channels, of which the power. Factors such as the intersite distance, frequency reuse factor, power control algorithm, and traffic. Dec 21, 2007 umts network planning, optimization, and interoperation with gsm is an accessible, onestop reference to help engineers effectively reduce the time and costs involved in umts deployment and optimization. Introduction umts is developed by 3gpp 3 generation partnership project a joint venture of several organization 3g umts is a thirdgeneration 3g. This paper describes standardized power control in umts and provides control theory aspects of the same with an extensive list of citations. So algorithm 2 is applicable when the environment of mobile environment is quite favourable and the channel fades slowly or hardly fade. In the closed loop mode, the mobile station transmitter power is controlled by a signal from the base station. The physical layer administrates all radio communication.
Umts through wcdma can be summarized like a revolution of the air interface accompanied by a revolution in the network of their architecture. Pdf outerloop power control in a live umts network. In such systems, in fact, many users transmit over the same radio channel using the same frequency band and time slots so. The universal mobile telecommunications system umts is a third generation mobile cellular system for networks based on the gsm standard. Based on this estimate, the mobile unit adjusts the transmit power accordingly. The openloop power control is employed at the beginning of a connection, and an uplink dedicated channel dch or common packet channel cpch, is not yet allocated. Power control in wireless cellular networks mung chiang electrical engineering department, princeton university prashanth hande electrical engineering department, princeton university. Wcdma occupies 5 mhz channels and has defined formats for elements such as synchronisation, power control and the like cdma technology. Easily clear job interviews and college exams after studying these multiple choice.
This survey article describes and discusses relevant aspects of umts power control with emphasis on practical issues, using an automatic control. Pdf power control with antenna array processing for umts. Fredrik gunnarsson and fredrik gustafsson, control theory aspects of power control in umts, control engineering practice, volume 11, issue 10, pages 111125, october 2003. Request pdf control theory aspects of power control in umts the global communication systems critically rely on control algorithms of various kinds. The proposed algorithm can mitigate received sir variations when channel fading changes slowly. The cdma technology used in umts relies on accurate power control techniques, not only for maximising the battery life of mobile terminals and maintaining signal quality, but also as an important means of optimising system capacity by controlling interference.
In universal mobile telephony system umtsthe third generation mobile telephony system just being launchedpower control algorithms play an important role for efficient resource utilization. The handover and power control algorithms have been developed and implemented in the framework of a system level e umts simulator developed under the ist seacorn project. Objectives are higher data rates, lower latency on the user plane and control plane and a packetoptimized radio access technology. Pdf simulating soft handover and power control for. Evaluation and modeling of power control information in a 3g. It specifies a complete network system and the technology described in it is popularly referred as freedom of mobile multimedia access foma. The umts world is an 3g mobile system news and information provider. Outer loop power control sets the signal to interference ratio sirtarget and inner loop power control adjusts the peer entity transmit power so that measured sir fulfills the sirtarget. Downlink power control parameters when downlink power control parms f1 is pressed, the following parameters are displayed in the downlink power control parameters middle menu. In modern cellular communication systems, power control plays a fundamental role for efficient resource utilization. Umts network is called a third generation network3g. Developed and maintained by the 3gpp 3rd generation partnership project, umts is a component of the international telecommunications union imt2000 standard set and compares with the cdma2000 standard set for networks based on the competing cdmaone. Where things start to get interesting is with the power dynamics. Figures for the three main bands in use are given below.
Developed and maintained by the 3gpp 3rd generation partnership project, umts is a component of the international telecommunications union imt2000 standard set and compares with the cdma2000 standard set for networks based on the competing. Wcdma is deployed in the 850 and 1900 of the existing frequency allocations and the new 3g band 17002100 should be available in the near future. The power level numbers vary according to the gsm band in use. Interferensi adalah fitur yang melekat pada sistem cdma dan tidak dapat dihindari, namun mekanismenya harus dipastikan di level minimum yang diperlukan untuk melayani. The output power is 1 db less than the standard power when the rru3959rru3959w is located at a height of 3500 m to 4500 m. The command is sent to the encoder inside the tc via the iu interface. Scribd is the worlds largest social reading and publishing site. Umts long term evolution lte technology introduction. Transport formats in umts radio network controllers. Outer loop power control sets the target sir for fast power control so that the desired quality is provided. Two special aspects of fast power control are presented as following.
Srnc performs dynamical control of power for dedicated channels, within limits admitted by crnc inner loop power control for some radio links of the ue connection may be. Umts technical umts universal mobile telephone service is a third generation 3g mobile system being developed by etsi within the itus imt2000 framework. Control theory aspects of power control in umts request pdf. User equipment the umts standard does not restrict the functionality of the user equipment in any way. Radio resource management in 3g umts networks diva. Uplink power control is the ability of the ue transmitter to set its output power in accordance with the measured downlink path loss, which is determined by higher. Research open access an energy efficient semistatic. Introduction power control is a crucial radio network function in cellular systems. Keywords lte, uplink, power control, fractional power control. Umts works on wcdma, cdma2000 and tdscdma implementations by 3gpp. This reduces resources and interference, hence, increases the systemwide.
In universal mobile telephony system umts the third generation mobile telephony system just being launched power control algorithms play an important role for efficient resource utilization. The accuracies required for gsm power control are relatively stringent. The future lines that are considered in the present, and other comment that already are in their last phase of development in the field of the mobile technology. Pdf queuebased power control in umts systems tommaso. The successful trial, deployment, operation and troubleshooting of 3g or umts infrastructures and applications is the. Simulation results indicate that fractional power control is advantageous compared to the conventional open loop power control in terms of mean cell throughput. The mobile unit measurement is part of the open loop power control while the base station measurement is part of the closed loop power control. The book explains the rf engineering aspects of umts, key elements of the 3gpp specifications, and practical operation of umts networks.
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