TWI377856B - Precise sleep timer using a low-cost and low-accuracy clock - Google Patents

Description

VI. Description of the Invention: [Technical Field to Which the Invention Is Ascribed] The present invention relates to wireless communication I罟 such reference vibratory power control. , Kao, Shane is about [previous technology] There is an algorithm for the high-precision clock # clock. This allows low accuracy to calibrate low accuracy timings, and these techniques have the same thing, producing = as accurate as the master clock. Wrong ~ 疋 about the master clock correction low precision wear at = 2 such as WTRUs and other mobile

IrU 2 extended the electric scale slave (four) heavy material. Should be designed in yRu correction and hard as minimal as possible, can also extend the battery life by the reduced power consumption of the forest activity time , = during this time interval, some power months m skin off or some reduction The operation of the power mode. Configuring the UMTS allows the WTRU to operate in a *_____ 可 ( (4) function, when a paging or other proprietary connection is not in progress, the WTRu only needs to perform certain functions occasionally to maintain synchronization and communication with its associated base station. Provides a secret interval that allows the WTRU to minimize the amount of money. This is achieved by a WTRU that performs a discontinuous reception (DRX) operation, where the wtru cycles between "sleep" and "wake-up" periods. Unwanted power consumption methods and hardware are _ during sleep. In the process of dumping, these methods and hardware that require maintenance and communication with their associated base stations are temporarily turned back on. Most handheld WTRUs today include a low accuracy 1377856 instant clock (RTC) in addition to the high accuracy master clock. The main clock is typically implemented using a temperature controlled crystal oscillator (TCX〇). RTC typically consumes far less energy than the TCXO consumes, which makes it desirable to use RTC instead of TCXO to provide timing functionality during DRX. However, there are four problems with the use of RTC during DRX. First, RTC is typically operated at a significantly reduced rate (e.g., 32,768 kHz to 76 8 megahertz) compared to tcxo. Second, the frequency accuracy of the RTC is very low compared to the frequency accuracy of the TCX〇. Third, due to different environmental reasons such as temperature changes, the frequency shift of rtc is greater than the frequency shift of tcxo. Fourth, RTC typically operates asynchronously with TCX〇. For these reasons, the typical RTC during DRX is not sufficient to provide timing functionality separately. SUMMARY OF THE INVENTION WTRUs include high power consumption, high speed, high accuracy, and high stability reference resonators such as TCXO with lower power consumption, lower speed, lesser accuracy, and lower stability RTC. The TCXO symbolically provides the timing function of the WTRU. Chatter is unable to provide a timed ship with sufficient accuracy and accuracy for the WTRU. To minimize power consumption and use discontinuous reception_〇 operations, TCX〇 is turned off, and the RTC provides the WTRU's timing function during some of these shutdown times. The correction and synchronization method between tcx〇 and = ensures that the timing function provided by the age during tenderness is sufficiently accurate and accurate. [Embodiment] As used herein, the recording axis is purely limited to the device of the user, the station, the mobile station, and the fixed <1> Name, base station, including 1377856 = not limited to Β·_ 'base station control weaving, pick-up point or in the wireless environment. Although some of the specific embodiments are combined with the third generation partner (WPP) system, they can be used in other wireless systems. ” and (4) “High power and high-precision hybrids are turned off during the face-to-face mode.., _sf... The combination of different methods and low-accuracy vibrations. By using low-power vibration (4), _Long battery life. Typically, low

^ and low-precision (4) H operate at higher power and high accuracy vibrators for lower frequency orders of magnitude. For example, in the dance industry, the "RTC operation of the low-power clock is used in industrial fresh 32.768 thousand _ ' compared with the high-power and high-accuracy oscillators. 'The RTC operates at a reduced speed. The aged RTC holds the wTRUs. Use the ability to use the RTC for shout mode operation for the general 'this implementation. The sleep timer (ST) algorithm is used to perform DRX timing and allow the primary TCXO to be turned off' to reduce the power consumption of the standby WTRU, Tcx 〇 It can be cleared during the sleep interval. When TCX0 is turned off, the low-power crystal oscillator or RTC is used to control the timing until the TCX is turned on again. For this purpose, the standard crystal silk-based instant clock Or other standard clock circuits are used for RTC. The RTC is combined with the sleep timer algorithm, which overcomes the use of the RTC algorithm used in the calendar mode by the frequency measurement and scheduling solution. The RTC can be any suitable or clock, which does not change the algorithm; only its parameters are changed. The invention is applied to the DRX statement and is provided for

UMTS standard. However, * Å Å Å Å Å Å 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 Figure 1 is a flow chart showing the operation of the WRU in the active mode of the active 11 and the DRX 12. In the active mode 1, the WTRU provides the full communication Wei represented by the communication device 13. In spite of the reliance on the communication, in general, the WTRU element is fully operational, actively using τ 〇 ΐ ΐ 7 by the synchronization device μ with its timing device 15 timing. The RTC function guessed by the rtc device 18 can be operated 'but the communication device 13 is primarily dependent on Tcx 〇 17. The field WTRU is in DRX mode 12, and the synchronization and timing functions are illustrated by the synchronized two-way device 25 but are shown at a reduced level. It is necessary to recognize the event of the master_operation mode, and the communication device 23 maintains the pass T with reduced synchronization and timing capabilities, which reduces the #β's and makes it dependent on the RTC 28. The first figure shows the same non-operation mode' and the physical components of the different Tcx〇s 17, 27 and the lamps 18, 28 thus described are executed by the same physical device. Infuriate, execute the cell and re-enter the ___= in the paging, then the tenderness depends on the sleep mode, the active and DRX components and according to the algorithm into the "ugly tree gift algorithm including the main affair, the general system Operation with DRX operation - active cycle 2 shirts maintained under TCXO operation and maintenance transfer to RTC operation 1377856

The decision that the active-cycle component includes the synchronization update' and whether the WTRU should enter the DRX mode determines whether the WTRU should enter the DRX mode is based on a predetermined inactive rule; ^, the example of entering the DRX mode includes the end of the session. The predetermined time interval between the scheduled time _ inactivity, the cell search activity for which no sufficient signal is located, and the predetermined number of consecutive unsuccessful cell search activities. A particular criterion is a function of the WTRU.

In a specific specific customs towel 'RTC's measurement of Wei Xing. ^, RTC frequency measurement can be avoided because this can be performed in the DR component. The WTRU enters the DRX mode when the relative inactivity interval is determined by the WTRU when deciding. The DRX component' RTC fresh measurements are performed on a periodic basis to maintain synchronization and a decision as to whether to return to active mode.

The components of Figures 3 and 4 can be implemented using integrated circuits, such as integrated circuits (ASICs), multiple ICs, discrete components, or ICs (a combination of pole discrete components) tailored to a particular application. Figure 2 The sleep timer algorithm (10) makes (4) the aspect of the round-in and output signals, the clock and the DRX touch length are measured by the input τ rate 83' calculation is performed for the wake-up and sleep position, and the most iron is used to generate The number of wakeups 93〇TCXO_, TCX〇shutdown and next pager, or synchronization update is the output of algorithm 80. θ) Sleep timer H and other connections (4) calculus (4) Interaction side is (4) Graph box®. The _ timing H itself is based on the _ timing control described later, and the block diagram of the third figure shows the interaction of the sleep timer with other receivers. The components include a timing manager (1), a circuit ΐΐ 2 ” path 113, a receiving chopper circuit 114, a frequency estimation circuit, a circuit waver 7 1377856 116, a digital analog converter (DAC) 117, and a TCXO 118. A timing correction (FTC) circuit 121, and a master clock 126, an RTC 127, and a sleep timer 128. This circuit implements an algorithm responsible for obtaining and maintaining frame synchronization of the receiver. ADC circuit 112, AGC circuit 113, and receive filter Circuit 114, frequency estimation circuit 115, loop filter 116, DAC 117, and TCXO 118 form frequency estimation loop 131. Timing manager m, adc circuit 112, aGC circuit 113, receive filter circuit 114, and FTC circuit 121 provide frames. Synchronization loop 132. In this particular embodiment, 'sleep timer 128 receives signals from master clock 126 and rtc 127, which ultimately provide a signal to turn TCX 〇 118 on and off. The input system is as follows. 1) Master clock (MC) If there is 76 8 megahertz (the wafer rate), the nominal frequency '· and 2) RTC has a nominal frequency of 32,768 Hz. The control aspect is as follows: (10) The frame is extracted from the DRX and the length is taken as a method. Input; 2) under The event is the binary input of the paging block or the synchronization update block and the first Mc pulse starting from PO. The output is as follows: CXC) The electric service is turned off _ between '2) tcxo boot display with RTC pulse Mode and 3) next--! gt or synchronous update location power __ wake-up time can be P〇 or synchronized ft paging block, next chip rate _ some _= alone, h MC Pulse (10) in sleep mode _ performed a selection measurement and checks the user activity of the acquisition channel, the implementation of the cell cycle and enter the main _ heart and then the WTRU leaves the sleep loss to measure the strongest cell, such as the first block _ In any of the four (4), Figure 4 shows the layer j DRX cycle_operation in the DRX mode. The ship is called the phase, and the sleep timer is measured in the first part of the RTC frequency: the two different parts of the operation are operated at new intervals.苴 第 第 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在 在® PQ #作. These two parts - the ~ opening method, although other calculations can be used, in the example of wealth After the frame offset is synchronized, the update step is eight, and the step is further _ 幻 64. — f shows that 'many RX warm-up period 83 is shown, which is generally in other activities 2 == 72'173 or Synchronization_block (6) before. During sleep, such as sleep, before the B warm-up period, the synchronization update period 162 is before the synchronization update block 164. RX-preheating is a parameter bribe TCX〇 for early 5 msec TCXO Preheating, which is approximately equal to the number of MC (20X) pulses at 5 milliseconds, the number of pulses in this particular embodiment is set to 384, 〇〇〇. The DRX is intended to identify periods of relative inactivity, which are turned off by the various WTRU components and go to sleep, providing the opportunity for the power to be saved. The eWTRU is informed that it must wake up to receive the transmission of the data. DRX is used for idle. Mode and connection mode for the CELL_PCH and URA_PCH states of the connected mode. During DRX, when the command is set by the RRC (Radio Resource Controller) based on the system data, the WTRU must wake up at P〇s. 1377856 One, when the dirty is responsible for scheduling _, the specific one ^ two two corresponds to the - call block, the paging block is composed of many frames 2 or 4 shot guides (7) push the frame into the material guide channel times) Block; 2) a gap period consisting of 2, 4, or 8 frames, where the physical source is used by other channels; and 3) from 2 to 16 pages of paging content The paging channel (pCH) block consisting of frames. When DRX is used, the timing diagram of the pi-blocks that have been provided by the WTRU to monitor only one P0 in each tender cycle is shown in Figure 4. The length of the dish ^ can vary from 8 to 512 frames, such as in the empty Mode, possible DRx cycle lengths are G.64, 1.28, 2.56, and 5.12 seconds; and in CELL/URA-calendar state 'possible DRX cycle lengths are 0.08, 〇16, 〇32, 〇64, 丨28, 2%, and 5.12 second.

During DRX, the WTRU should periodically update its frame and timing synchronization to be able to successfully read Pis and perform cell reselection measurements. Therefore, the periodic DRX activity of layer i includes cell reselection and related measurements, monitoring pis; and maintaining frame and timing synchronization. Right the WTRU detects that it is paged via the associated pi, which reads pcH to access the paging content, otherwise it returns to sleep. If the TCXO is operated continuously, it will consume 2.0 amps maximum current from a 3.0 volt nominal DC power supply or a 6 wattage power supply. For additional power savings, tcx〇 can be turned off during DRX sleep. When the TCXO is turned off, the sleep timer is used to schedule the number of wake-ups of the TCXO for the start of the p〇s or synchronization update. The power consumption of the RTC compared to the TCXO is typically insignificant, with an i milliampere size from the volts DC supply of II or 3 Q milliwatts. The use of RTC is accompanied by two problems. First, the resolution does not satisfy some wireless ^_ requirements. For example, the wide-age jade multiple access (w cdma) time division duplex (TDD) weights 'RTC ❺ 义 义 rate is 32 768 secret Jobs at 3 (four) micro = minimum resolution or ln i9 wafers or 3" pass samples (10) million mega records) ° - syllabus RTC depends on the accuracy ' rt called the frequency is different, the gap is as much as (10) parts per million - Maximum deviation. The third frequency stability is low. Therefore, the problem is that the frequency shift rate is not higher than [+/_]〇.3 million knives per clock or 0.005 millionths per second. This frequency shift rate is typically room temperature (four) The worst case of ΤΧΟ), which uses specially cut crystals due to poor temperature sensitivity. Because these shakers are not as special as the TCXO, they are less expensive. The sleep timing H algorithm consists of two parts, 1TC Fresh and Sleep Timer Schedule. Frequency measurements are performed periodically during the DRX cycle to overcome frequency accuracy and frequency stability issues, and are partially compliant with WTRU age requirements to accurately schedule DRX events when the TCXO is turned off. No need for any frequency correction for RTC' only need to accurately measure the frequency of RTC. In active connection mode, RTC solution measurement is not required, because it seems to be ON' RTC freshly only before and during the training period. For what is needed. The update rate should be such that the total fresh accuracy should be around G1 parts per million. The sleep timer algorithm interacts with the timing manager _, the next ρ〇 1377856 or the synchronized update output identifies the timing administrator MC pulse at the same time as the start of the PO or synchronized update after wakeup. Since the PO of the timing administrator starts to input the p〇 after the recognition wakeup to the sleep timer algorithm, if the FTC changes the frame timing after the synchronization update, the indicated P0 start time is related to the updated timing. The sleep timer algorithm compares instant clock frequency measurements with sleep timer scheduling. Regarding the instant clock frequency measurement, Fig. 5 is a timing chart of the RTC frequency estimation window according to the present invention. To accurately measure the number of RTC frequency master clock pulses 271 is calculated over a long period of time 272. The main clock has a frequency of 76.8 megahertz, which is a 2 晶片 chip rate. Because this clock is phase-locked to TCX 〇, its worst accuracy is 〇 1 part per million 'because there is no correction to RTC. The accuracy of the TCX〇 does not affect the accuracy of the rtc frequency measurement. The accuracy of the RTC frequency measurement can be increased as desired by increasing the frequency estimation window size. The accuracy of the RTC frequency estimate for .1 million is required to measure (1) millions of master clock (MC) pulses 271.

When the frequency estimation window is selected to be 4096 RTC pulses ("tics"), it has a nominal RTC frequency of 32,768 Hz and a main clock frequency of 76 8 megahertz including 9,600 nano MC pulses. The beginning and end of the drunk estimation window The pulse η touches, the RTC pulse 271 ❾ starts the initial MC pulse count 〇 at the beginning of 帛 4096 RTC pulses 271, the Mc count stops, and the Mc counter value is used for frequency estimation. The frequency estimation window is maintained for about 125 milliseconds or 13 Frame, in active connection mode, this frequency = count is not executed 'except only before entering the human cycle. In this case, the frequency measurement is sent to the DRX cycle anywhere in the last _ bribe before entering the DRX cycle. During the period, the frequency measurement is performed during each synchronization update period, 12 1377856 frequency measurement and 妓 should occur in the last i3 frame of the synchronization update _, so that tcxo has the greatest possible _ to determine. The mosquito fresh material is used for the next Paging block.

Regarding sleep piracy scheduling, Figure 6 shows the timing chart of the sleep timer scheduling. The sleep cycle determines the two cycle events of each DRX cycle; the next wake-up time of TCX〇; and the next P〇 or The next synchronized update block begins, no matter which one is the next event, the time (specific MC pulse), to locate these events in the case of I's exist - the amount and many methods to apply the simple method. A timing diagram of the event is shown at the bottom of Figure 6. TIC A : The first RTCTic after P0. TIC b=brtc : Turn on RTC tic of TCX0, Brtc sets RTC tics s starting from p〇 (calculate each synchronization update or DRx cycle length change TIC OCRTC: used to locate the next p〇 or synchronization Update the rTc tic during the DRX start of the block (calculated for each synchronization update). KRTC (= 4096) The number of mTC tics indicates the frequency estimation period (constant). DRXP: This parameter indicates the frame-by-frame method. The current distance from the next event to the next event's record-transfer input and DRX cycle lengths have different values. These values are provided in Table 1. DRX cycle length KMC: MC (20X) pulses per DRX period ( For all degrees list) KRTC : The number of RTC pulses used during frequency estimation, which is set to 13 1377856 4096.

Mmc: The number of measured MC pulses in the RTC frequency estimation window (measured during each synchronization update). Amc: measured from the beginning of the current p〇 to TicA]^(: number of pulses (measured per DRX cycle).

Brtc: The tcxo sister time expressed as an RTC pulse before the start of the next P〇 or synchronization update block, which is approximately equal to 5 milliseconds (expressed as 164 RTC tics). CMc. The number of counted MC tics from Crtc (TicC) to the next paging block or synchronization update block, the start of the cMC pulse and the start of the first paging block or the first wafer of the synchronization update block Almost at the same time. At the beginning of the parent paging block, the next wake-up time is calculated, which can be done as follows: 1) measure the number of MC pulses from p〇 to the next RTC pulse (TIC in), AMC; 2) found in Table 1. DRXp; and 3) Calculate Brtc, CRTC, and CMC using the equations in the equation. Figure 7 is a flow chart of the TCX〇 shutdown procedure during DRX. After the paging block _ (dip 301) is measured Amg (pour 3G2), followed by the calculation of Brtc, cRTC and cMC (step 3 〇 3), these calculations are followed by reading picH (step 304) 'and then for the decision paging Whether the patrol (9) is positive (the step dog is positive or not) the WTRU is paged or changed in some settings indicated by the BCCH, so 'if pi is positive, the WTRU will read the PCH channel to find ρι positive What is the value? If PI is positive, 'PCH is read (step 3 j υ, and whether the data read from the PCH indicates paging or Β (Β^ 1377856 312). Right The data read from the pCH indicates that the paging CCH 经 is as determined in step 312, TCX0, the maintenance operation, or the DRX mode ends (step 313). If Π is not positive, as determined in step 3〇5, Or if pcH does not indicate that the material or BCCH correction is determined as determined in step 312, then a decision is made as to whether the current positivity correctly follows the synchronous update (step 321). If the current P0 correctly follows the synchronous update, the method waits until the AFC and TFC converges (step 322), and when AFC and current convergence decide whether to self-regulate / (4) Declare that the distance from the beginning of the event is greater than 1 frame (step 323). If the distance from the AFC/TFC convergence statement to the start of the next event is greater than 1 frame, the TCXO is turned off and the DRX mode continues (step 324) 1 from the AFC/TFC convergence statement to the next event start distance is not less than 1 frame as determined in step 323, then TCX0 maintains operation but drx mode continues. If the current P0 does not follow the synchronization update, As determined in step 321, the proximity search measurement is performed until completion (step 341), and a decision is made as to whether the distance from the current 0 to the next synchronization update is less than 17 frames (step 342), if from the current P0 The TCXO is turned off and the Drx mode continues until the next synchronous update start distance is less than 17 frames (step 324). If the distance from the current 〇 to the next synchronous update is not less than 17 frames, the TCXO maintains the operation. However, the DRX mode continues. In operation, the next sleep timer event is scheduled TCX 〇 shutdown, which is outlined in the flowchart. As seen in the flowchart, 'every drx cycle has three final scheduling conditions: l) TCXO shutdown , WTR U maintains the DRX and applies the sleep timer algorithm; 2) TCX0 maintains operation due to the conditions shown in the flowchart and the WTRU dimension 15 1377856 is held in DRX, the clock reference used is TCX〇 and the unused sleep timer algorithm ; and 3) TCX maintains operation and the WTRU must leave DRX. In this case, the WTRU has been paged or BCCH correction data is present. Table 1 DRXp is longer than the next event DRX period (frame) Next event DRXP (frame) 32,64 '128 ' 256 ' 512 paging block DRX cycle length ·16 8,16 Synchronization update block DRX cycle length The paging block DRX cycle length synchronization update block Ν / Α〇 * 〇 (*) as explained above for this situation TCX 〇 is the last step of the method is the wake of the next event, the wake-up method is as follows 1 Turn on TCX0 at time Brtc, Brtc waits for the last ρ〇 pulse ^ wait until time CRT (: ; 3) from CRTC: start calculating cM (: main clock pulse; 4) at & main clock pulse 'time approximate and lower - The beginning of an event is the same, that is, the next-to-time slot of the second-time slot; and 5) the method of repeating each of the ancestor cycles until the WTRU leaves the DRX cycle. , ^ Fa · - The advantage is actually the method of judging the money, this method avoids the real demand, timing accuracy can be controlled by changing the length of the measurement interval or > test 4 • clock frequency. This simplicity comes from the fact that the method has a low accuracy clock but only measures its frequency. , Bay ^ 16

Λ/OJO [Simple diagram of the diagram] The diagram of the scheme is a flow of remuneration operations that are not in the active U and Shun 12 modes of operation. The picture shows the interaction between the input and output signals used by the sleeper algorithm and the synchronous algorithms of other receivers. Figure 3 is a block diagram showing the effect of sleep timing. Figure 4 is a timing diagram of Layer 1 processing. Figure 5 is a diagram of the RTC frequency estimation window. Figure 6 is a timing diagram of the sleep & time lag event. Figure 7 is a flow chart showing the steps of the recorder shutdown during DRX.

Tics Pulse Amc The number of measured MC pulses from the beginning of P0 to Tic A (measured per DRX cycle). [Main component symbol description] DAC digital analog converter FTC frame timing correction circuit PCH paging channel PICH paging guidance channel RTC instant clock TCXO temperature control crystal oscillator DRX discontinuous reception MC master clock pi paging guidance P0 paging opportunity WTRU wireless transmission / Receiving unit

BrTc The tcxo wake-up time represented by the RTC pulse 17 1377856 before the start of the next PO or synchronous update block, which is approximately equal to 5 milliseconds (expressed as 164 RTC tics).

Cmc from CRTC (Tic C) to the next paging block or synchronous update block starting with s·}* different 14 (: tics number, the beginning of the CMC pulse and the first paging block or the first update block The beginning of the chip is almost simultaneous. DRXP This parameter indicates the distance from the current p〇 to the next event in frame mode, which has different values depending on the next event input and the length of the DRX cycle. These values are provided in Table 1.

Kmc MC (20X) pulse number per DRX (listed for all DRX cycle lengths).

The number of RTC pulses used by Krtc during frequency estimation' is set to 4〇96. Mmc The number of measured MC pulses in the RTC frequency estimation window (measured during each synchronization update). The first RTC Tic after TIC A P0. TIC B=BRTC Turns on the RTC tic of the TCXO. The BRTC sets the number of ^;!^ tics starting from p〇 (each synchronous update or DRX cycle length change calculated). TIC C = CRTC RTC tic (calculated for each synchronization update) during the drx used to locate the next P0 or synchronous update block. 11 Active mode 12 DRX mode 13, 23 communication device 14, 24 synchronization device 1377856

15 ' 25 Timing device 17, 27 TCXO 18, 28 RTC device 80 Sleep timer algorithm 83 RTC frequency measurement 88 Calculation of wake-up and sleep position 93 Generation of wake-up times 111 Timing administrator 112 ADC circuit 113 AGC circuit 114 Receive filter circuit 115 Frequency Estimation Circuit 116 Loop Filter 117 DAC 118 TCXO 121 FTC 126 Master Clock 127 RTC 128 Sleep Timer 131 Frequency Estimation Loop 132 Frame Synchronization Loop 164 Synchronization Update Block 171-174 Paging Block 181--183 RX Pre Hot period 191 during sleep 271 main clock pulse 272 long time period 19

Claims (1)

^// 856 power mode of operation; the reference oscillator is a high power and high accuracy oscillator; the controller is configured to use the reference capping during the low power mode of operation for synchronization updates; The controller is configured to determine the completion of the synchronization update based on an automatic frequency control (AFC) and a frame timing correction (FTC) convergence, and to utilize a time frame as the selected threshold. A wireless transmit/receive unit (WTRU) as claimed in claim 3, wherein k, a temperature-controlled crystal oscillator; the 7-to-temperature crystal pull-off TXO); Control|| She uses the TCX0 during this low power mode of operation in response to a paging opportunity (P0) or a synchronized update. 5. The wireless transmit/receive unit (WTRU) of claim 1, wherein the controller is configured to use the reference oscillator during the low power mode of operation to perform a cell reselection measurement. 6. The WTRU is configured to use the formatted time frame to establish wireless communication, as in the application for the wireless transmission/reception unit (10) described in item 5, where the controller is configured. The reference oscillator is used during the low power mode of operation for synchronization update; and / 21 1377856 the controller is configured to converge according to an automatic frequency control (AFC) and a frame timing correction (FTC) Determining the completion of a synchronized update and utilizing a time frame as the selected threshold for the difference between the completion of the synchronized update and the next program requiring the use of the reference oscillator, and for Seventeen time frames are utilized as the selected threshold for the difference between the completion of the cell reselection measurement and the next procedure requiring the use of the reference oscillator. 7. The wireless transmit/receive unit (WTRU) of claim 6, wherein the reference oscillator is a temperature controlled crystal oscillator (TCXO); the RTC comprises a room temperature crystal oscillator (RTXO) And the controller is configured to use the TCXO during the low power mode of operation in response to a paging opportunity (PO). 8. The wireless transmit/receive unit (WTRU) of any one of clauses, wherein the WTRU is configured for use by a third generation partner project (3Gpp) compatible system. Equipment. 9. A method of wireless communication, comprising: providing a wireless transmit/receive unit (WTRU) having a reference oscillator for synchronizing communications, a real time clock (RTC), an active mode of operation, and low power operation a mode in which the reference oscillator is used in the active mode of operation and using the RTC in the low power mode of operation and selectively using the reference capper; and 22 1377856 during the low power mode of operation, When the decision is made and the difference between the determination is greater than the completion of the procedure and the difference between the use of the reference and the program is used, the selected threshold value of the gate of the reference surface is sequentially _ The reference vibrator. =_Touch the 9 items of the tearing method, shoot, and draw a closer look - temperature controlled crystal mmii (TCX_ as a quenching vibrator. 11. The method described in claim 9 of the patent, wherein · formatted Time frame to establish the wireless communication; the low power operation material includes - discontinuous touch (DRX); the reference vibrating is used for synchronization update between the low power operation modes. Root, an automatic frequency control (AFC) And - frame timing correction (FTC) to determine the completion of a synchronization update; and 5 b update & after the use of a time frame as the selected fe boundary value to determine to close the reference The method of claim n, wherein a temperature controlled crystal oscillator (TCX〇) is provided as the reference oscillator; and the dish is used in response to the low power wheel mode The beer is synchronized and updated. 13. If the application is turned to 9_green, the towel is used in the low-turning of the reference, and the cell is re-selected for measurement. In order to make 23 1377856 14. The method described in the item, which is constructed by a formatted time frame Wireless communication; during the low power operation mode, the reference oscillator is used for synchronization update; determining the completion of a synchronization update according to convergence of automatic frequency control (AFC (10) and frame timing correction (FTC); For the completion of the synchronization update and the use of the reference engine, the difference _ difference 'money-time frame as the selected threshold; and the selection and completion of the measurement for the cell The reference vibrator-down-program _ difference makes the oblique seven-frame as the selected critical value. 15. If the application of the paste 14th machine is green, its towel, lifting wtru a temperature control a crystallizer (TCXO) as the reference oscillator; and use the TCX0 during the low power mode of operation in response to a paging opportunity (p〇). 16. As claimed in claim 9-15 The method of the item, wherein the WTRU is provided as a user equipment for a third-generation partner project (3〇ΡΡ) compatible system.