This paper show application of fga power control on wcdma. During this project, the different phases passed from the election of wcdma like the access method for umts will appear. You can perform the entire inner loop power control in the uplink test by piecing the test segments together. Power control is essential for the smooth operation of a cdma system. Power control in wireless cellular networks mung chiang electrical engineering department, princeton university prashanth hande electrical engineering department, princeton university. Wcdma wideband code division multiple access plays the best competitive role in the present world. Power control is considered as an important means to combat nearfar fading effects and maintain acceptable connections in wireless. Umts through wcdma can be summarized like a revolution of the air.
Power control and soft handover are two essential techniques, which effectively increase the spec. The power of each individual user therefore, must be carefully controlled so that no one user is unnecessarily interfering with others who are sharing the. Because all users share the same rf band through the use of pn codes each user looks like random noise to other users. Dec 17, 2007 let us begin with hsdpa for which power control is significantly different from r99 channels.
Last week i wrote about umts power control with reference to r99 channels. The lmv226 is equipped with a buffered output which makes it wcdma rf power control suitable for gsm, edge, gprs and tdma cdma2000 rf power control applications. Power control, broadly speaking, is the intelligent selection of transmitter power output in a communication system to achieve good performance within the system. This chapter studies the adaptive openloop power control of a cellular cdma system, which is overlaid in downlink by a narrowband signal. Pdf wcdma system standardization, interfaces and power control. R99 downlink power control downlink power control means change of downlink power based on tpc command carried by uplink control channelul dpcch. 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. In order to maintain the received level at bs, a suitable power control technique must be employed in cdma systems. Efficient power control via auction in wcdma systems. Effect of power control commands delay in the wcdma mobile radio network are. Us6690652b1 us094,991 us499199a us6690652b1 us 6690652 b1 us6690652 b1 us 6690652b1 us 499199 a us499199 a us 499199a us 6690652 b1 us6690652 b1 us 6690652b1 authority.
But other way if students have to speak they have to increase decrease their voice depending on which row they a. Power control pc is an essential function of cellular. In the closed loop mode, the mobile station transmitter power is controlled by a signal from the base station. Introduction to wcdma wcdma for umts wiley online library. Thus selfoptimizing uplink outer loop power control with dynamic change of sirmax, based on current. Auto mode is used to run a single test segment as specified by 3gpp ts 34.
Power control in cdma 2000 is more complex than is95. The chapter presents the main system design parameters of wcdma and gives brief explanations. 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. In lte, power control takes place both in downlink and uplink. Let us begin with hsdpa for which power control is significantly different from r99 channels. A telecommunications system employing wcdma technology in a preferred embodiment, utilizes compressed mode techniques to allow a mobile station to take measurements on another frequency in preparation for interfrequency transfer.
Since power control consists of reducing the share of power transmitted for the closein users, it is possible that a power control law devised on the bases of the cir. Comprehesive coverage of umts 3g news, licensing, business developments, 3g wcdma telecommunication technology, multi media mobile phones and future communications. Uplink power control determines the average power over a dftsofdm symbol in which the physical channel is transmitted. Citeseerx wcdma common pilot power control for load and. Power control algorithms play an important role for efficient resource utilization. Important elements of the proposed algorithm are highlighted. Compared with utran the ul power control is slower.
Why is there no power control scheme in downlink for lte. Click download or read online button to get wcdma for umts book now. In conclusion, power control is extremely important in umts. It is the process in which cell tower and mobile phone collectively decide which minimum transmission power a phone could safely employ and still be heard by a cell tower.
Power control is essential in wcdma systems to provide satisfactory quality of service qos 1 and. The algorithm is based on a modification of the transmitted power update step size. A power control algorithm for 3g wcdma system citeseerx. Wcdma common pilot power control for load and coverage balancing. Umts power control open loop power control is the ability of the ue transmitter to sets its output power to a specific value. Todays post continues the discussion with reference to hsdpa and hsupa. The paper validates the feasibility of automating the setting of common pilot power in a wcdma radio network. Lmv225lmv226lmv228 rf power detector for cdma and wcdma. R99 uplink power control uplink power control means change of uplink power based on tpc command carried by downlink control channeldl dpcch. The received level fluctuates quickly due to fading.
To adjust the radiated power of mobile stations in a way that all received signals at the base station have the same sir for the same bit rate 2. This document describes power control equations used in cdma2000 1x spreading rate 1 standard and emphasizes performance issues related with these equations. Sep 20, 2007 summary this chapter contains sections titled. Near far effect efficient power control is very important for cdma network performance. Fga power control able to increase system capacity by. Demodulation of dch in site selection diversity transmission power control mode. List of channel power that does not change dynamically. Optimal implementation of novel wcdma uplink outer loop. Multiplexing of services with different quality requirements on a single connection, e. 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. As well as to know the technology kind that makes possible, for example, a videocall in real time. Feb 19, 20 need of power control low signal reception is due to improper power control.
Introduction summary of the main parameters in wcdma spreading and despreading multipath radio channels and rake reception power control softer and so. Loutfi nuaymi, xavier lagrange, philippe godlewski. Performance analysis of downlink power control in wcdma system dr. Openloop power control in cdma overlay springerlink. Characterization of downlink transmit power control during. Us6690652b1 adaptive power control in wideband cdma.
This kind of power control is used in almost all the mobile communication technology e. Clpc closed loop power control fpc fractional power control ftb fixed transmission bandwidth gipc generalized interference based power control gsm global system for mobile communications harq hybrid automatic repeat request ho hand over hspa high speed packet access iot it is the interference over thermal noise ipc interference based power. This site is like a library, use search box in the widget to get ebook that you want. Pdf outerloop power control in a live umts network. The pilot automation improves operability of the network and it is implemented with a control software aiming for load and coverage balancing. The umts world is an 3g mobile system news and information provider.
Introduction during soft handover, the power control procedure is more complicated because there are at least two bss involved. So algorithm 2 is applicable when the environment of mobile environment is quite favourable and the channel fades slowly or hardly fade. As you see in the figures below, both downlink dpcch and uplink dpcch slot has a special field called tpc transmission power control field. Hsdpa does not have fast power control as in r99 dl dpch. Coverage planning amounts to determining the cell coverage pattern by means of setting the common pilot channel cpich power of the cells. However, power control is just as important for hsdpa. Where things start to get interesting is with the power dynamics. By controlling supply voltages for the rf power amplifier in a cdmawcdma cellular phone, you can improve the pa efficiency, minimize heat, and dramatically extend the phones datatalk time. Power control in wcdma the purpose of power control pc is to ensure that each user receives and transmits just enough energy to prevent. Cdma rf power control combination with a directional coupler.
Power control for power drifting can improve the soft handover performance in the downlink. Downlink capacity, soft handover, power control, wcdma. Individual copies of the present document can be downloaded from. To ensure good performance, power control is implemented in both the uplink and the downlink, which means that both the output powers of the handset and the base station are frequently. In order to change the value of the dl power control mode 1 parameterthrough mod cellsetup, the cell shall be firstly deactivated through dea cell. When the relev and quality is good, the transmission power of. Therefore the picture below should explain you on which channels in dl and ul, power control takes place. Wcdma system standardization, interfaces and power control. It is needed to minimize the interference in the system.
Wcdma, outer loop power control, uplink received signal strength indicator ul rssi, maximum allowed signal to interference ratio sirmax, transmission. Wcdma for umts download ebook pdf, epub, tuebl, mobi. We need to control the transmission power of each user. Coverage planning for optimizing hsdpa performance and. Jun 18, 2012 power control can be used against shadow fading and fast fading. Optimal implementation of novel wcdma uplink outer loop power. Voice capacity offered is very high due to interference control mechanisms, including frequency reuse of 1, fast power control, and soft handover. The receivers having the new proposed equalizers 7 and the conventional rake receiver are considered. 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. This is achieved by selecting any one of the test segments referred to as test steps in the standard from the test segment menu and then initiating the measurement. Power control mechanism is an important issue for code division multiple access cdma systems which helps in achieving higher capacity, power control allows to minimize the transmit power while keeping the.
This control is called the transmission power control control power. Wcdma technology provides some advantages for the operator in that it allows the data, but also improves the voice of base. This paper investigates the power control mechanism in the context ofthird generation multimedia multirate wideband cdma wcdma mobile communications. They way it takes place in downlink and uplink will become evident in a little bit, as we go further down the discussion. Gsm, in the 2g bands, and has adopted wideband cdma wcdma in the 3g bands.
Accurate transmitter power level can be achieved by using optional power control loops, which send appropriate transmitter power control tpc commands through dedicated feedback channel. Reducing the interference results in direct increase in system capacity. Fundamental limitations of power control in wcdma, report no. Power control is essential in wcdma systems to provide satisfactory quality of service qos and to combat several problems. The design contains a lot of flexibility to allow power control at different levels. Wcdma common pilot power control for load and coverage balancing kimmo valkealahti, albert hoglund, jyrki parkkinen, and ari hamalainen nokia research center, fin00045 nokia group abstract the paper validates the feasibility of automating the setting of common pilot power in a wcdma radio network. Inner loop power control happens implicitly in hsdpa based on adaptive modulation and coding amc. Config rf settings rf power downlink output channel power ior 93. At the start of the call phone uses reasonably high power settings and then. This project tries to introduce itself in the physical implementations that make possible the denominated third generation mobile technology. Wcdma is a third generation mobile wireless technology offering much higher data speeds to mobile and portable wireless devices than commonly offered in todays market.
Rf power reduction for cdmawcdma cellular phones abstract. In contrast to utran based on wcdma however the requirements for ul power control are more relaxed as a similar nearfar problem of utran does not exist. Power control can reduce the system interference and improve the spectrum utilization and prolong the service time of ms battery. Summarizes and surveys current lte technical specifications and implementation options for engineers and newly qualified support staff. Concentrating on three mobile communication technologies, gsm, 3gwcdma, and ltewhile majorly focusing on radio access network ran technologythis book describes principles of mobile radio technologies that are used in mobile phones and service. To adjust the radiated power of mobile stations in a way that all received signals at the base station have the same sir for the same bit rate to reduce cochannel interference by concurrent users. We first present the system model and get the sufficient condition for the existence of feasible power assignment. It is used for setting initial uplink and downlink transmission powers when a ue is accessing the network.
Us6597679b1 control of compressed mode transmission in. Several new parameters have been added to the equations to support better performance of the algorithms. Fast transmitter power control is essential in wcdma mobile radio networks, in particular on the uplink without it, a single overpowered mobile station ms could block the whole cell 8. Blocking of distant users nearfareffect exceeding reasonable interference levels without pc received ue1 power levels would ue2 be unequal ue3 ue1 ue2 in theory with pc ue1 ue2 ue3 received power levels. Wcdma common pilot power control for load and coverage. Teacher need not increase decrease her voice but speak in loud voice so all students can hear her. Abstract the issue of software downloads is currently a hot topic in.
Download wcdma wideband code division multiple access, an itu standard derived from code division multiple access cdma is officially known as imt2000 direct spread. Dec 09, 2007 in conclusion, power control is extremely important in umts. This whole process forms a cyclic loop and this kind of control loop is called closed loop in control system theory. Pdf the outer loop power control olpc in wcdma systems allows to. In this paper, an evolution of the power control algorithm is proposed for the thirdgeneration wcdma system. Uplink power control performance in utran lte networks. It describes the need for power control and its implementation and soft and softer handover. Adaptive power control has widely been used in dscdma systems to overcome the socalled nearfar problem. Coverage planning is an important engineering task in deploying umts networks implementing both high speed downlink packet access hsdpa and release 99 r99 services. Modified adaptive step size power control algorithm for. Fredrik gunnarsson and fredrik gustafsson, control theory aspects of power control in umts, control engineering practice, volume 11, issue 10, pages 111125, october 2003. A new quasioptimum power control scheme for downlink in. Pa modules the device is active for enable hi, otherwise it is in a low power consumption shutdown mode. Wcdma can offer a lot more voice minutes to customers.
There are two ways to control the transmission power. The uplink performance of the network is decisively influenced by power control. By doing that the rapid change in the radio channel is handled. The notion of good performance can depend on context and may include optimizing metrics such as link data rate, network capacity, outage probability, geographic coverage and range, and life of the network and network. Selfoptimizing uplink outer loop power control for wcdma.
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