Adaptive power control algorithm for 3g cellular cdma. An example of implementation algorithm using dl preamble is shown. Closed loop power control is used in wireless communication networks to compensate for fast fading, timevarying channel characteristics, and to reduce mobile battery power consumption. The core of this control algorithm is embedded inside the xcubespn7 and xcubespn8 firmware package available on the st web site. Its objective is to maximize capacity by minimizing power and interference.
This approach works well as long as there are sufficiently frequent. Pdf power control algorithms in wireless communication. Further, we combined outer loop power control scheme with the open. Umts uplink closedloop power control closedloop power control procedures in umts are standardised by 3gpp 9. Control engineering 61 lecture 6 outer loop setpoint profile generation gain scheduling feedforward and 2dof design system inversion problem feedforward for simple models zero order, first order, second order, oscillatory input shaping iterative update of. Control engineering 61 lecture 6 outer loop setpoint profile generation gain scheduling feedforward and 2dof design system inversion problem feedforward for simple models zero order, first order, second order, oscillatory input shaping iterative update of feedforward runtorun, cascade loop. Abstractwe propose a reinforcement learning rl based closed loop power control algorithm for the downlink of the voice over lte volte. Pdf outerloop power control in a live umts network. The ide tools supported are iar workbench, keil and ac6. Dualloop control strategy for gridconnected inverter with. The process feedbacks in figure 3 are shown schematically as one. Comparative analysis of power control algorithms for uplink. Standardised inner loop power control closed loop power control clpc is available only in dedicated channels in both uplink and downlink.
Jul 12, 2012 the control boxes perform pid algorithms. Both open and closed loop power control methods are used. Speed control for turbinegenerator of orc power generation system and experimental implementation. Closed loop power control since the forward and reverse links are considered to. Stability of rate and power control algorithms in wireless. Open loop power control vs closed loop power control. Inner loop control outer loop control received signal measured sir fer target sir transmitter power updown command base station behavior 0.
Inner loop power control is responsible for adjusting the transmitting power to fulfil the minimum sir target set by outer loop power control. Open loop power control inner loop power control outer loop power control commercial in confidence 2 20081127 3. The outer loop control frequency bias algorithm droop and dead band settings must match the droop and dead band settings of the generators. Stability of rate and power control algorithms in wireless cellular networks. Regular paper optimal implementation of novel wcdma uplink outer loop power control algorithm angelo gary markoc. Outer loop power control in a wideband cdma system core. Umts power control open loop power control is the ability of the ue transmitter to sets its output power to a specific value. No single variable algorithm such as rss will satisfy. Therefore, to assist the outer loop power control, the number of retransmissions actually used for transmission of a transport block is signaled from the node b to the rnc.
After hsupa power control enhancement is enabled, joint optimization on inner loop and outer loop power control is performed to decrease the interference among nonqossensitive ues. After that, closed loop power control will be applied. In 3, the outer loop 1 might be a pure p control, loop 2 a pi control, loop 3 another p control, and loop 4 is a p translation to switching times for the pwm. However, existing methods widely use modelbased power optimization algorithms in the outer loop along with. The parameters of the pi controller for the outer and inner loops are given in table 2.
The outer voltage control loop is adjusted by the modified. Optimal implementation of novel wcdma uplink outer loop power. This closedloop power control is used after an initial phase that uses an openloop power control. Scheme over functionality of the outer and inner power control loops. Three types of power control algorithms are employed in wcdma. Sirbased power control algorithms for wireless cdma. 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. The pi controllers for the inner and the outer loop are designed using the small statespace averaging technique model and using sisotool in matlab 2528. A prerequisite for using this library is basic knowledge of the c programming language, three phase motor drives and power inverter hardware. Abstractpower optimization and control for gridcoupled wind energy conversion systems wecs has been extensively studied for variable speed wind turbines.
Based on analysis of uplink air interface overload problems, it has been concluded that existing uplink outer loop power. In this paper, a new outer loop power control algorithm based on fuzzy theory is proposed. In wcdma frequency division duplex fdd at uplink a feedback controlloop is implemented in form of an inner loop power control ilpc and an outer loop power control olpc. This paper focuses on inner loop power control techniques which is a category of closed loop power control algorithms in the uplink umts. The closed loop control structure in is95 one of the currently implemented standards used in wireless networks consists of an outer loop algorithm that. After that, closedloop power control will be applied. It indirectly controls the uplink and downlink transmit power by increasing or decreasing the target sir value. Open loop power control closed loop power control is used in combating the fast fading effects, generally caused by multipath fading. 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. Control algorithm for equal current sharing between parallel. During a call, the sir target varies between implemented lower sirmin and upper boundaries sirmax, which are fixed values on radio network control station rnc.
There are three types of algorithm for power control, investigated in,,,, which are implemented in wcdma system. A dualloopbased parallel power supply system scientific. When the ue is not in soft handover, only one tpc command is received in each timeslot. Only one or two of the three terms of the pid algorithm might be implemented. Forward power control contains inner loop and outer loop power control, and the inner loop and outer power control work together target fer get from ecam calculate fer set target ebnt value detect forward ebnt insert power control bit. Nov 23, 2011 its objective is to maximize capacity by minimizing power and interference. Foschini miljanic distributed power control simplest power control solving nearfar problem. The required bler depends on both radio conditions, and.
Qlearning algorithm for volte closed loop power control. A power control algorithm for 3g wcdma system citeseerx. This parameter defines the initial sir target value of outer loop power control algorithm. This paper focuses on innerloop power control techniques which is a category of closed loop power control algorithms in the uplink umts. A new adaptive power control algorithm for umts communication technologies. Outer loop inner loop slow fast sir rot rottarget sirtarget channel power fig. The outer loop adjusts the current reference in order to maintain a regulated bus voltage independently from the load or input voltage variations. Closed loop power control for lte uplink diva portal. The control algorithm for the gridside pwm inverter is illustrated in figure 2. Iterative distributed power control dpc, at iteration k. An example is 28, which adds a term proportional to the time derivative of.
Variance minimization stochastic power control in cdma. Power control in wcdma is a closedloop pc which is a combination of outer. Pdf the outer loop power control olpc in wcdma systems allows to. The outer loop controls congestion by setting the sirtarget to the inner loop.
It happens at a rate of 1500 hz to combat fast fading. A novel outer loop power control algorithm based on fuzzy. In this paper, we propose a new adaptive power control algorithm for in umts. If a dch is configured, the outer loop, which is an implementationspecific algorithm, may continue to. Selfoptimizing uplink outer loop power control for wcdma.
The inner layer is called reverse inner loop power control rilpc, while the outer layer is called reverselink outer loop power control rolpc. Deals with power control, channel assignment and handoff decisions. Power control algorithms in the downlink of the tdd mode and in both link directions of the fdd mode are based on a closedloop control. Comparative analysis of power control algorithms for. The outer loop adjusts the current reference in order to maintain a regulated bus voltage independently from the. The inner layer, rilpc, typically requires the base station receiver to periodically obtain some measure of the snr being received on a given connection, compare it with a target snr and send a one. The lte power control mechanism constitutes of a closed loop component operating around an open loop point of operation. In 3, wu extended zanders problem formulation to cdma systems by reordering the number of users in different cells. Power control and if you want to have some handson experience of these, i would. Closed loop power control is needed as estimating the uplink losses based on. Both the ideal and a more realistic case modeled by including delay, error, and power headroom reporting were. The current ratio of the parallel circuits can be set arbitrarily.
The open loop component compensates path loss and shadowing through fractional power control enabling a tradeoff. Cdma2000 1x power control algorithm telecommunications. In this way, overall power control process form a loop closed loop. The rnc can use this information as part of the outer loop to set the sir target in the inner loop. To avoid such types of errors, it is often convenient to test the loop with simple i. As possible solution for wcdma uplink overload problems, a novel uplink outer loop power control algorithm with dynamic change of sirmax has been proposed. In this thesis an algorithm for the outer loop power control has been studied and evaluated by simulations in a matlab simulator called curt cdma umts radio network simulator. Closed loop power control is used in wireless communication networks to compensate for fast fading and timevarying channel characteristics, and to reduce mobile battery power consumption. The outer loop controls congestion by setting the sirtarget to. This mechanism is also termed as fast power control as it deals with the fast fading. Loop power control an overview sciencedirect topics. Oneshot receive power equalization by bs control 19921993. According to the principle of inhibiting resonance by using damping resistance, and using equivalent transformation, a dualloop control strategy for gridconnected inverter with lcl filter was proposed in this paper, this. The dualloop control method, in which innerloop is the current and outerloop is the voltage, is proposed to design a highefficient precise numerical control parallel power supply system, it operates at input voltage of 24v, output voltage of 612v and output current of 04a.
The dual loop control method, in which inner loop is the current and outer loop is the voltage, is proposed to design a highefficient precise numerical control parallel power supply system, it operates at input voltage of 24v, output voltage of 612v and output current of 04a. The uplink outer loop power control is responsible for setting a target sir in the node b for each individual uplink inner loop power control. In the proposed algorithm, the voltage set point for the outer voltage loop of converters i and ii are modified as shown in the block diagram of figure 7. However, existing methods widely use modelbased power optimization algorithms in the outer loop along with linear control techniques in the inner loop. Control algorithm for equal current sharing between. Based on this estimate, the mobile unit adjusts the transmit power accordingly. Power control needs to reduce intercell interference level at the same time achieve a required sinr level. Icv voltage loop crossover frequency loop and the outer voltage control loop are both simplified, making it much easier to achieve high crossover frequency in both loops. The block diagram of figure 4 shows the outer and inner control loops for each converter. 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.
For details of lte specific power control, you have to refer to ts 36. The closed loop control structure in is95acurrentlyimplemented cdmastandardsusedin wireless networks consists of an outer loop algorithm that. A new power control algorithm for cellular cdma systems. Furthermore, it lacks abilities to cope with rapid variations in fast fading channels. All gos are encouraged to look at dead bands, droop setting and outer loop controls that may prevent or squelch primary frequency response and take actions to correct. The proposed algorithm can mitigate the oscillations. In the example above, if we check the loop by printing 1 star, instead of 10 by substituting 10 with 1 in the condition of the loop, we immediately notice that the loop would print 2 stars, instead. The inner loop controls the sirlevel by changes in the transmission powers. So algorithm 2 is applicable when the environment of mobile environment is quite favourable and the channel fades slowly or hardly fade. Therefore, it causes oscillations when the radio channel is unchanged. An example of application of the adaptive step principle is.
The inner loop power control located in the node b bases its decision on the sir target set by the outer loop power control located in the rnc. Reverse link outer loop power control with adaptive. Outer loop power control is used to maintain the quality of communication at the level of bearer service quality requirement, while using as low power as possible. The value corresponding with the difference of bler and blertar, processed by fuzzy membership function.
In wcdma frequency division duplex fdd at uplink a feedback control loop is implemented in form of an inner loop power control ilpc and an outer loop power control olpc. Closedloop power control is used in wireless communication networks to compensate for fast fading, timevarying channel characteristics, and to reduce mobile battery power consumption. Finally, the interaction between successive interference cancellation sic receivers at the physical layer and power control, which is a layer 2 radio resource management issue, is studied. It is used for setting initial uplink and downlink transmission powers when a ue is accessing the network. The input stage is typically controlled using an outer voltage loop for bus voltage regulation and an inner control loop to shape the current according to a sinusoidal waveform. Power control in the cdma2000 system consists of a reverse link closed loop power control rclpc, a reverse link outer loop power control rolpc, a forward link closed loop power control fclpc. Different parameter settings for this algorithm has been used and evaluated. Inner loop power control in the uplink is the ability of the ue to adjust its output power in accordance with one or more tpc transmit power control commands received in the downlink. Ecen 615 methods of electric power systems analysis. Auto mode is used to run a single test segment as specified by 3gpp ts 34. Based on analysis of uplink air interface overload problems, it has been concluded that existing uplink outer loop power control has difficulty. Dualloop control strategy for gridconnected inverter. As possible solution for wcdma uplink overload problems, a novel uplink outer loop power control algorithm with dynamic change of. According to the principle of inhibiting resonance by using damping resistance, and using equivalent transformation, a dual loop control strategy for gridconnected inverter with lcl filter was proposed in this paper, this.
For example, in a buckderived regulator, the current loop has to deal only with the inductor pole, while the output. You can perform the entire inner loop power control in the uplink test by piecing the test segments together. Nov 15, 2005 the inner layer is called reverse inner loop power control rilpc, while the outer layer is called reverselink outer loop power control rolpc. Outerloop power control the outerloop power control is responsible for adjusting the sir target, based on some particular measured parameters such as bler. All gos are encouraged to look at dead bands, droop setting and outer loop controls that may prevent or squelch primary. In this thesis we propose a novel power based algorithm for switching between ptp and ptm in order to deliver mbms content with minimum power consumption. Different values of the path loss compensation factor are investigated in the range 0. Optimal implementation of novel wcdma uplink outer loop. There are three types of algorithm for power control, investigated in 410, which are implemented in wcdma system. Hence, the power control algorithm aims to reduce transmission power and interference level, and to maximize system capacity.