CN1459944A - Unit searching mode and device used for wide band code division multi job access system and device - Google Patents
Unit searching mode and device used for wide band code division multi job access system and device Download PDFInfo
- Publication number
- CN1459944A CN1459944A CN02120154A CN02120154A CN1459944A CN 1459944 A CN1459944 A CN 1459944A CN 02120154 A CN02120154 A CN 02120154A CN 02120154 A CN02120154 A CN 02120154A CN 1459944 A CN1459944 A CN 1459944A
- Authority
- CN
- China
- Prior art keywords
- unit
- code
- phase
- detector
- sampling point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
Abstract
A unit search method for WCDMA receiving system is characterized by use of a three-stage unit search, and includes matching an incoming signal from base station, over-sampling it N times at the chip speed, outputting N over-sampled points, under-sampling it N times, outputting its N sample points to parallel N signal pathes, and thransmitting them through 3 processing stages to complete a trial. A unit searcher is also disclosed, which has simple hardware.
Description
Technical field
The invention relates to a kind of demal multitask access system (code divisionmultiple access that is used for, CDMA) unit method for searching and device, more be particularly to a kind ofly be used for the wide band code division multitask and access (wideband code division multiple access, W-CDMA) the unit method for searching and the device of system, the effect (the effects ofclock offset) of imperfect sampling effect and sampling frequency deviation in this method and the device reduction system simultaneously.
Background technology
The demal multitask access unit formula system (cellular systems) that uses a direct sequence type exhibition frequency division sign indicating number multitask to access (direct sequence spreadspectrum code division multiple access) technology increases channel capacity significantly.The attention that suction phase is worked as in nearest Mobile Communications system research of this system.Generally speaking, because utilization again (frequencyreuse) character of frequency, the bandwidth efficiency of demal multitask access system (bandwidth efficiency) is more superior compared with other multitask access system (access with TCM access as frequency division multi-task).In addition, unit planning (cell planning) is quite simple at demal multitask access system.Therefore, demal multitask access unit system will be following main flow.Particularly third generation cooperative programme (Third generation partnership project, 3GPP) the wide band code division multitask access/frequency division duplexing (W-CDMA/FDD) system has been used in one of standard of a kind of IMT-2000 of being used for third generation system.
In the modular system that a demal multitask accesses, (userequipment UE) is called as " unit search " (cellsearch) as the method for searching best-of-breed element by user's set.The unit is searched extremely important fast, start shooting time of delay (switched-on delay) (the initial search), increase standby (standby time) (idle state search) in order to reduce this user's set and changing hand (handover) (operate condition search, active mode search) maintenance good communication link quality.
See the United States Patent (USP) number the 6th of awarding to people such as Shou, 038, No. 250, its title be " the demal multitask of initialization synchronized method and direct sequence type accesses the receiver of the asynchronous cellular system of trunk desk " (Initial Synchronization Method And Receiver for DS-CDMAInter Base Station Asynchronous Cellular System) propose one use initialization synchronized method in the unit of being searched at a high speed and the receiver demal multitask that is used for the direct sequence type access the asynchronous cellular system of trunk desk.One Base Band is accepted signal and is input to a matched filter and is relevant to a spreading codes, and this spreading codes is provided by the spreading codes generator.One signal electrical power is calculated the electrical power that device calculates the relevant output of matched filter, and exports this result to the synchronous time-histories resolver of long code (long code synchronization timing determiner), door hurdle value calculator (threshold value calculator) and long code validator (long code identifier).During initial cell was searched, this spreading codes generator was exported a short code, and this short code is jointly in the control channel of each base station.The synchronous time-histories of long code is by after the decision, and each forms the chip of the synthetic spreading codes sequence of N chip of a part in succession by displacement and output.
See the United States Patent (USP) number the 6th of awarding to people such as Nystrom, 185, No. 244, its title is " unit is searched in the demal multitask and accessed communication system " (Cell searching in a CDMAcommunications system), be set forth in the unit and search during the demal multitask accesses communication system, more efficient code scheme needs a long code and frame time-histories.Sign indicating number set with MQ row (MQ-ary) code word size, wherein this code word comprises the set from a Q short code, and this yard set is that definition is to specific characteristic.This initial characteristic that is satisfied does not have the cyclicity drift for this code word thereby produces an effective code word; Other the characteristic that is satisfied is between long code message and effective code word, have one to one and should claim (mapping), and this encoder can find to appear at disturb with the code word of the moving at random of noise (thereby finding frame time-histories) and this transmission (promptly, be relevant to long code and represent message (long code indication message)), have the accurate and rational complexity on some degree.
See the United States Patent (USP) number the 6th of awarding to people such as Kim, 289, No. 007, its title is " method that accesses the acquisition search unit base station of Mobile Communications system in asynchronous demal multitask " (Method for Acquiring A Cell Site Station in Asynchronous CDMACellular Communication Systems), that propose a group code (group code) and element number and be the multitask transmission and be used as a guidance code (pilot code), this guidance code is used for the differentiated base station that the demal multitask of asynchronous unit accesses communication system.Use the multitask transmission code, disturb owing to using two guidance codes to reduce.The method that the unit base station is searched in acquisition that accesses the Mobile Communications system in asynchronous demal multitask comprises a base station controller, a plurality of mobile stations and base station, with use not homotactic different base stations, the step of the method for this search unit base station comprises (a) and specifies the group code of this unit to specify the group code of this unit to transmit the guidance code of this homophase (inphase) channel and 1/4th (quadrature) channel as guidance code (c) multitask of 1/4th (quadrature) channel of base station as the guidance code (b) of homophase (inphase) channel of base station and produce a homophase and 1/4th guidance code.
Now please refer to Fig. 1, this figure will help to understand third generation cooperative programme (3GPP) wide band code division multitask and access/frame structure (frame structure) of frequency division multi-task system.At first, wide band code division multitask in third generation cooperative programme (3GPP) accesses/the frequency division multi-task system in, the unit search is finished by three phases (three stages) for the typical case goes up, this three stage comprises two specially designed synchronizing channel (synchronization channel, SCH) and common pilot channel (common pilot channel, CPICH).In the phase I 110, (pfimary synchronization channel, PSCH) 1111 are used for time slot (slot) synchronously to elementary synchronizing channel.This elementary synchronizing channel 111 includes elementary synchronous code, and (primary synchronization code PSC) is defined as ac
p, wherein " a " (=± 1) relies on diversity that base station transmits and transmits (diversitytransmission) and whether exist and decide.In second stage 120, (secondary synchronization channel, SSCH) 121 are used for frame/code group (frame/codegroup) identification to the secondary synchronization channel.This secondary synchronization channel 121 includes the secondary synchronization sign indicating number, and (secondarysynchronization code SSCs) is defined as ac
s, wherein coefficient a is equal to the coefficient of elementary synchronizing channel.In the phase III 130, this common pilot channel 131 is used for passing down the decision of disturbing code (downlink scrambling code).As shown in the figure, in 10 milliseconds of (ms) frames, comprise 15 time slots, and because in this system, used the speed of per second 3.84 1,000,000 chips (Mchips/sec).Therefore, comprise 38400 chips in each frame, just comprise 2560 chips in each time slot.In addition, this elementary synchronizing channel and this secondary synchronization channel length comprise 256 chips and only transmit at the beginning on this time slot border.
The wide band code division multitask that is used for third generation cooperative programme (3GPP) accesses/and traditional unit search of frequency division multi-task system can be divided into the kind of two kinds of summaries: and formula (serial) is searched and catheter type (pipelined) is searched in regular turn.As shown in Figure 2, formula search in regular turn is before the new search of the next one begins, need in regular turn through three synchronous phases, be respectively (slotsynchronization) (2) frame synchronization/code group judgement (frame synchronization/code groupidentification) (3) disturbing code judgement (scrambling code identification) synchronously of (1) time slot.Now please refer to Fig. 2 (a), this figure one is used for the reduced graph of formula (serial) unit search process in regular turn of traditional three stages.What for simplicity, complete three a stages search will be claimed is a test (trial).In the formula unit is searched in regular turn, test not overlapping, till this searches successfully, that is to say, can only be arranged in action a stage in the time, have only a square frame (block) 211, square frame 212 moving (a certain stage of a certain test of each box indicating herein) in the i.e. time, therefore consume lower power loss with square frame 213, but the longer search time of cost.
In addition, shown in Fig. 2 (b), the three phases that catheter type (pipeline) is searched then carries out respectively simultaneously.For introducing the catheter type search in detail, this figure one is used for the reduced graph of traditional three stage catheter type unit search process methods.In catheter type was searched, the detection of different phase was operated simultaneously, that is to say that between test and the test be overlapping.For instance, square frame 311, square frame 321 and square frame 331 are in same test.Significantly, in catheter type is searched, in a regular time, how possible test can be arranged, also therefore obtain one and search faster.Certainly the cost of being paid is bigger power pin consumption.For the accelerator module search, therefore, this catheter type search is more extensively used by the people.Note that for the catheter type search not having extra hardware unit compared with formula unit search in regular turn needs.For instance, if we suppose that each needs 10 milliseconds time in stage, if this unit is searched the K time success of the test, then searching needed unit search time each time is (K+2) * 10 millisecond (ms); The following formula in regular turn search of comparing then needs K * 30 millisecond (ms).
Yet, be generally used in the multitask of third generation cooperative programme wide band code division to access/two basic assumptions are arranged in the prior art of the unit search of frequency division multi-task.The first, the sampling of exporting at chip-matched filter (chip-matched filter) is perfectly (desirable sampling).Yet in fact, the sampling of exporting at chip-matched filter is perfect (being imperfect sampling).The second, be accurately to know (promptly being not have sampling frequency deviation (clock drift or clock offset)) in the chip time of transmitter to receiver), just, this entering signal carrier frequency is all set the skew that does not have frequency.In fact, frequency shift (FS) (frequency offset) comes from the frequency instability of the crystal oscillator of user's set, and for user's set, this entering signal carrier frequency may have the side-play amount of frequency.Frequency shift (FS) causes two effects (1) phase deviations (2) sampling frequency deviation at Base Band, and wherein the part of sampling frequency deviation is not taken into account in the prior art as yet.The sampling frequency deviation that this frequency shift (FS) causes is present between base station and the user's set.Now please refer to table one, this table is presented at the sampling frequency deviation that is produced under the situation of different frequency skew, for instance, and under the appearance of 12kHz frequency shift (FS), in 30 milliseconds of frames, have the skew of 0.69 times of chip time, be equivalent to the sampling frequency deviation of 6ppm.Therefore will cause control information and increase the unit search time.In the present invention, we focus on and solve the situation of this frequency offset less than 6ppm, but the present invention is not limited to this.
Fig. 3 (a) and Fig. 3 (b) are not prior art, but the inventor is at the observation figure that considers to export at elementary sign indicating number matched filter under the chip offset time effect that frequency shift (FS) causes.Show as Fig. 3 (a) and Fig. 3 (b) figure, owing under the sampling frequency deviation effect that frequency shift (FS) caused, disturb the result who increases between signal level reduction and chip.
Summary of the invention
Main purpose of the present invention provides a kind of unit method for searching, be used for demal multitask access system, more especially be used for wide band code division multitask access system, can be used in the reduction system imperfect sampling effect and sampling frequency deviation effect and finish the unit search fast.
Secondary objective of the present invention provides a kind of unit search device, be used for demal multitask access system, more especially be used for wide band code division multitask access system, in system, have and realize the unit search device under imperfect sampling effect and the sampling frequency deviation effect, and do not increase the complexity of hardware.
For reaching above-mentioned main purpose, the invention provides a kind of unit method for searching, be used for demal multitask access system, more especially be used for wide band code division multitask access system, reduce under imperfect sampling effect and the sampling frequency deviation effect.Wherein the phase I has an elementary synchronizing channel (PSCH) to be used for time slot synchronous; It is after time slot is synchronous that second stage has secondary synchronization channel (SSCH), is used for frame/code group identification; And the phase III has the judgement that common pilot channel (CPICH) is used for disturbing code.According to the present invention, this method comprises the following step: coupling (match) is from an entering signal of base station; This entering signal is crossed sampling N time and exported N sampling point (Y of sampling with a spreading rate
1(k), Y
2(k) ... Y
N(k)); This entering signal is fallen sampling and exported this N sampling point to N bar parallel signal path; Cross sampling point with this N and do phase I processing in regular turn, a second stage is handled and a phase III handles to finish a test (trial); Wherein, cross sampling point for this N and handle, in this second stage processing and the processing of this phase III different uses is arranged in this phase I by a control procedure.
This test of this unit search also comprises the following step: in handling in the phase I, a time slot that can obtain this entering signal is synchronous; In second stage is handled, detect a code group and the frame synchronization of this entering signal; In the phase III processing, select a disturbing code of this entering signal; Test this disturbing code and a hurdle value η
0Do one first authentication; If wherein this hurdle value is not exceeded, then this test writes off, and a new test will restart under not postponing; Otherwise selected this disturbing code carries out one second checking; If wherein this disturbing code is by this second checking, then test being tied to form merit, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).
According to a feature of the present invention, wherein this control procedure also comprises the following step: in handling in the phase I, choose an optimal sampling point in the sampling point excessively at this N.
According to another characteristic of the invention, wherein this control procedure also comprises the following step: in handling in the phase I, choose a sampling point randomly in the sampling point excessively at this N, and be sent to second stage processing and phase III processing, to carry out three phase process in this test.
According to a feature of the present invention, wherein this control procedure also comprises the following step: when handling in phase I processing, second stage processing and phase III, cross in the sampling point at this N at random and independently and choose a sampling point, in each stage of this test, to handle.
The present invention also provides a kind of unit search device, be used for demal multitask access system, more be used in particular for wide band code division multitask access system, this device is handled the channel of three phases, and wherein the phase I has an elementary synchronizing channel (PSCH) to be used for time slot synchronous; Second stage has secondary synchronization channel (SSCH) after time slot is synchronous, is used for frame/code group identification; And the phase III has the decision that common pilot channel (CPICH) is used for passing down disturbing code.The one unit search device that is used for demal multitask access system according to the present invention, this unit search device comprises: a chip matched filter, in order to the entering signal of coupling from base station; One sampling assemble is linked to this chip matched filter, in order to this entering signal is crossed sampling N time and exported N sampling point (Y of sampling with a spreading rate
1(k), Y
2(k) ... Y
N(k)); One falls sampler, is linked to this sampling assemble, crosses and to get o'clock to a phase I detector, a second stage detector and a phase III detector in order to export this N; This phase I detector is connected in this and falls sampler, be used to obtain this entering signal a time slot synchronous; This second stage detector is linked to this and falls sampler, in order to obtain a code group and the frame synchronization of this entering signal; This phase III detector is linked to this and falls sampler, in order to determine a disturbing code of this entering signal; One control assembly, be linked to this phase I detector, this second stage detector and this phase III detector, in this phase I detector, this second stage detector and this phase III detector, do different uses in order to control this N mistake sampling point; And an authentication ' unit, be linked to this phase III detector, be used to determine whether success of this test.
This authentication ' unit also comprises: a comparator is linked to this phase III detector, in order to test output this disturbing code and hurdle value η from this phase III
0Relatively; Whether one first decision assembly is connected to this comparator, correct in order to determine this disturbing code; If wherein this hurdle value is not exceeded, then this test writes off, and a new test will restart under not postponing, and anti-, if this hurdle value is exceeded, this disturbing code that is then determined promptly enters together step card unit; The unit of checking synchronously is linked to this first decision assembly, in order to verify this disturbing code; And one second decision assembly, be connected to this unit of checking synchronously, whether accept in order to determine this disturbing code; If wherein this disturbing code is by this second decision assembly, then success of the test, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).
According to a feature of the present invention, wherein should the phase I detector by the control of this control assembly, cross in the sampling point at this N and to choose an optimal sampling point.
According to a feature of the present invention, wherein should the phase I detector by the control of this control assembly, choose a sampling point randomly in the sampling point excessively at this N, and be orderly sent to this second stage detector and this phase III detector, to proceed this triphasic unit search.
According to a feature of the present invention, wherein by the control of this control assembly, this phase I detector, this second stage detector and this phase III detector are chosen a sampling point for crossing in the sampling point at this N at random and independently, to handle in each phase detector.
Description of drawings
The sampling frequency deviation of table one under the situation of different frequency skew, being produced.
Fig. 1 is that a wide band code division multitask that is used for third generation cooperative programme accesses/the simplification frame assumption diagram of frequency division multi-task system.
Fig. 2 (a) is that a wide band code division multitask that is used for third generation cooperative programme accesses/tradition of frequency division multi-task system formula unit method for searching in regular turn.(in this example, it is 10 milliseconds (ms) that the process time in each stage is made as).
Fig. 2 (b) is that a wide band code division multitask that is used for third generation cooperative programme accesses/traditional catheter type unit method for searching of frequency division multi-task system.(in this example, it is 10 milliseconds (ms) that the process time in each stage is made as).
Fig. 3 (a) and Fig. 3 (b) show, owing under the sampling frequency deviation effect that frequency shift (FS) caused, disturb the result who increases between signal level reduction and chip.
Fig. 4 is for using the control procedure of a kind of unit of the present invention method for searching.
Fig. 5 is a kind of unit method for searching according to first embodiment of the invention, and this method is to use the phase I to test (serial test in stage-1, STS1) method in regular turn.
Fig. 6 is the flow chart according to a kind of unit method for searching of first embodiment of the invention, and this method use phase I is method of testing in regular turn.
Fig. 7 is a kind of unit method for searching according to second embodiment of the invention, and this method is used every test grab sample (random sampling per trial, RSPT) method.
Fig. 8 is that this method is used every test random sampling methods according to the flow chart of a kind of unit method for searching of second embodiment of the invention.
Fig. 9 is a kind of unit method for searching according to the embodiment of the invention the 3rd, and this method is used every frame grab sample (random sampling per frame, RSPF) method.
Figure 10 is that this method is used every frame random sampling methods according to the flow chart of a kind of unit method for searching of the embodiment of the invention the 3rd.
Figure 11 searches framework according to a kind of unit of the embodiment of the invention, and this framework is for realizing unit of the present invention method for searching.
Figure 12 is according to a kind of signal model of the present invention.
Figure 13 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 0kHz, compare the performance plot of different units method for searching.
Figure 14 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 8kHz, compare the performance plot of different units method for searching.
Figure 15 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 12kHz, compare the performance plot of different units method for searching.
Description of reference numerals:
111: elementary synchronizing channel 121: secondary synchronization channel
131: common pilot channel 190: signal
200: unit search device 210: the chip matched filter
220: sampling assemble 230: fall sampler
235: control assembly
240: phase I detector 250: the second stage detector
260: phase III detector 270: comparator
271: door hurdle value η
0275: the first decision assemblies
280: authentication ' unit 290: synchronous authentication unit
295: the second decision assemblies
Embodiment
Fig. 4 is for using a control procedure of a kind of unit of the present invention method for searching.Because method and apparatus of the present invention is considered imperfect sampling effect and sampling frequency deviation effect in the system simultaneously.Therefore, the invention provides different embodiment to be applicable under the different situations.As figure, if having imperfect sampling effect but do not have sampling frequency deviation effect in the system, then this control procedure should import the unit method for searching one preselected strategy (pre-selection scheme).If have imperfect sampling effect and sampling frequency deviation effect simultaneously in the system, then this control procedure should import the unit method for searching in the one grab sample strategy (random sampling scheme).In the realization of device, this control procedure can be served as by a control assembly.
Fig. 5 is a kind of unit method for searching according to first embodiment of the invention, and this method is used preselected strategy, or the phase I of saying so is tested (serial test in stage-1, STS1) method in regular turn.As shown in Figure 5, in a certain stage of a certain test of each box indicating, for instance, the 511 expression phase I of square frame handle, and square frame 521 expression second stage are handled and the 531 expression phase IIIs of square frame handle.According to the present invention, in the different unit when always several 512 disturbing codes are used in down biography, and in whole system, reuse.This sign indicating number is subdivided into 64 groups again, and each group has 8 sign indicating numbers.Each frame is 38400 chips length and therefore expands to entire frame.Because this cell position is also asynchronous, this yard always begins its new cycle at this frame boundaries place.As shown in Figure 5, handle the process that three phases is handled in the method, describe the feature of its each phase process at this.In phase I 510, having an elementary synchronizing channel (PSCH), to be used for time slot synchronous.By use identical elementary synchronizing channel in search each time and by only transmit elementary synchronizing channel the time groove edge, time slot can be reached synchronously easily, by synchronously to this elementary synchronizing channel.What is more, the Ge Lei sequence of vague generalization class system (generalized hierarchical Golay sequence) is used as this elementary synchronous code owing to be easy to realize.Second stage 520 has secondary synchronization channel (SSCH) after time slot is synchronous, is used for frame/code group identification.Synchronous and code group identification can reach by detecting this secondary synchronization channel, and wherein this code group is called the secondary synchronization sign indicating number by the frequency of opening up of 16 quadrature spreading codes.In order to reduce the phase mutual interference, this secondary synchronization sign indicating number is for being orthogonal to this elementary synchronous code.In addition, for realizing frame/code group identification fast, this secondary synchronization channel further is encoded into one group of 64 code word, by one (15,3) (comma-free Reed Solomon code, CFRS), wherein each code word that should organize is by telogenesis one code group in free of discontinuities Reed Solomon code.Because Duan superperformance continuously, in case code group is designated, then this frame synchronization is finished.Phase III 530 has the judgement that common pilot channel (CPICH) is used for passing down disturbing code.After this code group was designated, by one of 8 sign indicating numbers in the selection a group, via using common pilot channel, this disturbing code can be determined simply.
Fig. 6 is the flow chart according to a kind of unit method for searching of first embodiment of the invention, and this method use phase I is method of testing in regular turn.In step 600, detect a entering signal from base station.In step 610, this entering signal is crossed sampling N time with spreading rate, and this mistake sampling back signal list is shown as Y
1(k), Y
2(k) ... Y
N(k).In step 615, sampling is fallen in this entering signal and export this N mistake sampling point to N bar parallel signal path.In step 620, carry out the phase I and handle, cross in the sampling point at this N and choose an optimal sampling point, wherein this N cross in the sampling point this optimal sampling point do not disturb occur under, cross the sampling value that has maximum in the sampling point at this N.In the phase I processing, it is synchronous that this optimal sampling point is used to obtain the time slot of phase I.One non-homologous (non-coherent) matched filter, wherein this matched filter is divided into plurality of sections, and the output of each section merges with its absolute value, is divided into four blocks and is used in the phase I as the synchronous detector of time slot as one.Non-homologous accumulation surpasses 15 time slots and suitably is found to be additive white Gaussian (additivewhite Gaussian noise).For preferable characteristic, enter the next stage above the border of a time slot is selected in the phase I.Phase I is chosen optimal sampling point use N * 10 millisecond (ms) in the sampling point excessively at this N in handling.And note that the used method of the embodiment of the invention by a control procedure, is crossed sampling point for this N and handled in this phase I as described in Figure 4, this second stage is handled and there is different uses this phase III in handling.
In step 630, this optimal sampling point passes carries out second stage processing and phase III processing.In step 640, after time slot was synchronous, this code group and frame synchronization can be finished in second stage is handled.This second stage is handled, and uses 16 matched filters to remove to detect this secondary synchronization sign indicating number.The accumulation (the coherent accumulation) of this people having the same aspiration and interest of second stage possible by this channel estimating of using from the phase I.After having gathered 15 secondary synchronization sign indicating numbers, they are relevant to this 64 free of discontinuities Reed Solomon code, and (comma-free Reed Solomon code, CFRS) code word, each code word have 15 possible circulation shift positions.So obtain 960 correlations.Therefore last, move about peaked this code group and circulation position and to be decided to be rational code group and frame boundaries respectively.In step 650, the phase III handle to be judged this disturbing code, by selecting of 8 sign indicating numbers in a group, wherein this code group second stage by identification.This phase III handles and judges possible disturbing code, wherein just do once and judge every 256 chips, and choose the corresponding disturbing code record of maximum institute once, at last, through 150 record backs (frame length), the value of this maximum number of votes obtained must be done one first checking and go to determine whether this disturbing code is correct.The value of this maximum number of votes obtained and a hurdle value η
0Relatively.This hurdle value η
0(constant false alarm rate) decides according to the fixed error alarm rate.In step 660, from this output and a hurdle value η of this phase III processing
0Make comparisons, whether correct in order to determine this disturbing code.If this hurdle value is not exceeded, this test writes off, and a new test will restart under not postponing.If this hurdle value is exceeded, this disturbing code promptly enters second checking.In step 670, for the second time verify whether this disturbing code is accepted, if wherein this disturbing code passes through, then success of the test, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).What is more, the selection of this sampling point realizes in regular turn, and each test is needed (N+2) * 10 millisecond (ms), and therefore if the whole unit search is just successful the K time test, required unit search time is (K+N+1) * 10 millisecond (ms).
Now please refer to Fig. 7, this figure is a kind of unit method for searching according to second embodiment of the invention, and this method is used every test random sampling methods.The main idea of this every test random sampling methods be N sampling point a test then on the basis of a test selected randomly going detect.Its motivation can have good benefiting under at random the appearance of use at sampling frequency deviation in the sampling point that exists.As shown in Figure 7, handle the process that three phases is handled in this method, the feature of its each phase process is similar to the explanation of Fig. 5.As shown in Figure 7, wherein the phase I 710 has an elementary synchronizing channel (PSCH) to be used for time slot synchronous.Second stage 720 has secondary synchronization channel (SSCH) after time slot is synchronous, is used for frame/code group identification.Phase III 730 has the decision that common pilot channel (CPICH) is used for passing down disturbing code.
Fig. 8 is the flow chart of a kind of unit method for searching according to a second embodiment of the present invention, and this method is used every test random sampling methods method.Now please refer to Fig. 8.In step 800, detect a entering signal from base station.In step 810, this entering signal is crossed sampling N time with spreading rate, and this mistake sampling back signal list is shown as Y
1(k), Y
2(k) ... Y
N(k).In step 815, sampling is fallen in this entering signal and export this N mistake sampling point to N bar parallel signal path.In step 820, to cross at this N and to choose a sampling point in the sampling point randomly and transmit this N and cross a sampling point that is selected in the sampling point and carry out the phase I and handle, second stage is handled with the phase III and is handled.Be noted that this detects a test and follows on the basis of a test, each sampling point is used for a test.But if cooperate Fig. 7 more this unit method for searching of clear interpretation second embodiment how to work.For instance, in test for the first time, at the square frame 711 of phase I, the square frame 721 of second stage and the identical sampling point of the square frame of phase III 731 tests, wherein this sampling point is chosen randomly to lower the effect of sampling frequency deviation.In case this experimental mistake, next new test will be tested the sampling point of picked at random once more.For instance, in test for the second time, at the square frame 712 of phase I, the square frame 722 of second stage and the square frame 732 of phase III also will be tested the sampling point of identical selection, and wherein this sampling point is chosen randomly.So test will be carried out always, be accepted by this synchronous proof procedure up to disturbing code.What is more, the selection of this sampling point realizes that in regular turn as traditional catheter type search pattern, therefore if the whole unit search is just successful the K time test, required unit search time is (K+2) * 10 millisecond (ms).
In step 830, it is synchronous that the phase I processing obtains the time slot of phase I.One non-homologous (non-coherent) matched filter, wherein this matched filter is divided into plurality of sections, and the output of each section merges with its absolute value, is divided into four blocks and is used in the phase I as the synchronous detector of time slot as one.Non-homologous accumulation surpasses 15 time slots and suitably is found to be additive white Gaussian (additive white Gaussian noise).For preferable characteristic, enter the next stage above the border of a time slot is selected in the phase I.
In step 840, after time slot was synchronous, this code group and frame synchronization can be finished in second stage is handled.This second stage is handled, and uses 16 matched filters to remove to detect this secondary synchronization sign indicating number.The accumulation (the coherent accumulation) of this people having the same aspiration and interest of second stage possible by this channel estimating of using from the phase I.After having gathered 15 secondary synchronization sign indicating numbers, they are relevant to this 64 free of discontinuities Reed Solomon code, and (comma-free Reed Solomon code, CFRS) code word, each code word have 15 possible circulation shift positions.So obtain 960 correlations.Therefore last, move about peaked this code group and circulation position and to be decided to be rational code group and frame boundaries respectively.In step 850, the phase III handle to be judged this disturbing code, by selecting of 8 sign indicating numbers in a group, wherein this code group second stage by identification.This phase III handles and judges possible disturbing code, wherein just do once and judge every 256 chips, and choose the corresponding disturbing code record of maximum institute once, at last, through 150 record backs (frame length), the value of this maximum number of votes obtained must be done one first checking and go to determine whether this disturbing code is correct.The value of this maximum number of votes obtained and a hurdle value η
0Relatively.This hurdle value η
0(constant false alarm rate) decides according to the fixed error alarm rate.In step 860, from this output and a hurdle value η of this phase III processing
0Make comparisons, whether correct in order to determine this disturbing code.If this hurdle value is not exceeded, this test writes off, and a new test will restart under not postponing.If this hurdle value is exceeded, this disturbing code promptly enters second checking.In step 870, for the second time verify whether this disturbing code is accepted, if wherein this disturbing code passes through, then success of the test, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).
Now please refer to Fig. 9, this figure is a kind of unit method for searching according to third embodiment of the invention, and this method is used every frame random sampling methods.As shown in Figure 9, also handle the process that three phases is handled in this method, the feature of its each phase process is similar to the explanation of Fig. 7.And this method of the 3rd embodiment is similar to the method for second embodiment very much, and two kinds of embodiment all adopt the grab sample strategy.Its main difference is in the system of selection difference of sampling point.This method of the 3rd embodiment is followed on the basis of a frame at a frame, rather than follows on the basis of a test a test as this method of second embodiment.That is to say that three phases all uses a sampling point of same grab sample in each test of the method for second embodiment.Yet each stage in each test of the method for the 3rd embodiment is independently used a sampling point of grab sample separately.
Now please refer to Figure 10, this figure is that this method is used every frame random sampling methods according to the flow chart of a kind of unit method for searching of third embodiment of the invention.In step 1020, to cross at this N and to choose a sampling point randomly and independently in the sampling point and transmit this N and cross a sampling point that is selected in the sampling point and carry out the phase I and handle, second stage is handled with the phase III and is handled.Be noted that this detects at a frame and follows on the basis of a frame, and does not lose its fairness.Handle in the phase I, second stage handles that to handle the sampling point tested may identical also possibility different with the phase III, that is to say, they at random and independently.But if cooperate Fig. 9 more this unit method for searching of clear interpretation the 3rd embodiment how to work.For instance, in test for the first time, the square frame 911 of phase I, the square frame 921 of second stage is tested a sampling point with square frame 931 (see figure 9)s of phase III, and wherein this sampling point is crossed sampling point Y from N randomly and independently
1(k), Y
2(k) ... Y
N(k) choose in.This sampling point be a frame then the mode of a frame be selected to lower the effect of sampling frequency deviation.In case this experimental mistake, next new test will be tested the sampling point of picked at random once more.That is to say that for the second time in the test, at the square frame 912 of phase I, the square frame 922 of second stage and the square frame 932 of phase III also will be tested the sampling point of identical selection, wherein this sampling point is chosen randomly.So test will be carried out always, be accepted by this synchronous proof procedure up to disturbing code.What is more, the selection of this sampling point realizes that in regular turn as traditional catheter type search pattern, therefore if the whole unit search is just successful the K time test, required unit search time is (K+2) * 10 millisecond (ms).
Figure 11 searches framework according to a kind of unit of the embodiment of the invention, and this framework is realized the unit method for searching of the present invention under the effect of imperfect sampling effect and sampling frequency deviation.
A kind of unit search device 200 is used for demal multitask access system, more is used in particular for wide band code division multitask access system, and this device is handled the channel of three phases.One chip matched filter 210 is in order to the entering signal 190 of coupling from base station.One sampling assemble 220 is linked to this chip matched filter 210, in order to this entering signal 190 is crossed sampling N time and exported N sampling point (Y of sampling with a spreading rate
1(k), Y
2(k) ... Y
N(k)).One falls sampler 230, is linked to this sampling assemble 220, crosses and to get o'clock to a phase I detector 240, a second stage detector 250 and a phase III detector 260 in order to export this N.This phase I detector 240 is connected in this and falls sampler 230, and a time slot that is used to obtain this entering signal 190 is synchronous.This second stage detector 250 is linked to this and falls sampler 230, in order to obtain a code group and the frame synchronization of this entering signal 190.This phase III detector 260 is linked to this and falls sampler 230, in order to determine a disturbing code of this entering signal 190.One control assembly 235, be linked to this phase I detector 240, this second stage detector 250 and this phase III detector 260, in this phase I detector 240, this second stage detector 250 and this phase III detector 260, do different uses in order to control this N mistake sampling point; And an authentication ' unit 280, be linked to this phase III detector 260, be used to determine whether success of this test.This authentication ' unit 280 also comprises a comparator 270, is linked to this phase III detector 260, and this disturbing code and the hurdle value η 0271 from this phase III compares in order to test output.Whether one first decision assembly 275 is connected to this comparator 270, correct in order to determine this disturbing code.Together step card unit 290 is linked to this first decision assembly 275, in order to verify this disturbing code.Whether one second decision assembly 295 is connected to this unit 290 of checking synchronously, accept in order to determine this disturbing code.The designer can be according to the situation of the effect of imperfect sampling effect and sampling frequency deviation, and controls this control assembly to different embodiments of the invention.
Further Computer Simulation is used in the comparison of the operating characteristic of the unit method for searching of inquiring into embodiments of the invention and conventional method.Emphasize the effect of imperfect sampling effect and sampling frequency deviation herein.All numerical result foundations: cross sampling point N=2, it is maximum that all general to rein in drift (maximum Doppler shift) be 185.2 hertz (being equivalent to user's set moves with the speed of 100-km/hr), the detection in each stage is 10 milliseconds (ms), Tp=250 millisecond (ms) and η
0With 10
-4False alarm rate (constant false alarm rate) set.In addition, the through-put power of this actual channel is following expression.At first, elementary synchronizing channel has identical power with the secondary synchronization channel, and the power ratio of this common pilot channel and synchronizing channel (elementary synchronizing channel+secondary synchronization channel) is fixed.The second, the power of this common pilot channel is 10% of overall transmission power.In other words, in the unit search process, 80% contribution of base station overall transmission power is disturbed in the unit.At last, a geometrical factor (geometry factor) G=(P
1+ P
Psc+ P
Ssc+ P
Pc)/P
xBe used in the position of this user's set of modularization in the unit.The G value that heals high represents that this user's set is more near near this base station.The distribution function of accumulating (CDF) of search time is used for inquiring into the characteristic pointer of different method for searching.
Now please refer to Figure 12, this figure is according to the present invention, a kind of signal model under the sampling frequency deviation effect that frequency shift (FS) caused.Signal r (t) use one fundamental frequency (base-band) that this receives is represented and is given as:
P wherein
Psc, C
Psc, P
Ssc, C
SscAnd P
Pc, C
PcBe respectively this elementary synchronizing channel, the power and the spreading codes of this secondary synchronization channel and this common pilot channel.G (t) expression Rayleigh fading (Rayleigh fading) gains, and it is a plural form, and h (t) is the square root (square root raised cosine shaping function) of a rised cosine function and to have be 0.22 around the factor in the wrong (roll-offfactor).
During being the chip of this user's set.τ is initial random delay and comes module with a stochastic variable, and this variable has whole that (0.5Tc distributes between 0.5Tc) equably.T
cDuring being the chip of this base station, and f
cBe the carrier frequency of this base station, f
ΔBe the frequency offset between base station and the user's set, ξ=f
Δ/ f
cIn addition, P
IWith P
XBe respectively and disturb (intra-cell interference) n in the unit
I(t) disturb (inter-cellinterference) n and between the unit
x(t) power, wherein n
1(t) and n
x(t) serve as zero with its assembly average of additive white Gaussian (additive whiteGaussian noise), and variance is one random process (randomprocesses) as in the unit and the model that disturbs between the unit.It is to be worth in this proposition that above-mentioned model has three observations.At first,, only consider smooth fading channel (flat fading) in order to simplify, Cai and only relevant for the channel of this unit search by the reception signal expression that is illustrated in us especially; All other channel is comprised in distracter n
1(t) or n
x(t) within.The second, ξ is expressed as the effect of sampling frequency deviation, and τ is expressed as imperfect sampling effect, and these all are that prior art is ignored.The 3rd, this model medium frequency skew comes from phase deviation and the sampling frequency deviation that propagation delay (propagation delay) is uncertain and frequency shift (FS) caused with imperfect sampling effect and originates from identical oscillator.
Figure 13 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 0kHz, compare the performance plot of different units method for searching.Wherein " ideal " is used for representing desirable sampling.As shown in the figure, imperfect sampling causes serious operating characteristic to destroy, and particularly (signal to noise ratio is in case SNR) (one less gain G value) in lower signal noise ratio.In this figure, when all search strategies and signal noise ratio gain G were 6dB, 90% chance (occasions) can be done in 110 milliseconds.On the other hand, when the signal noise ratio gain G is 0dB, unit method for searching (STS1) according to the first embodiment of the present invention can be finished 90% search rate in 300 milliseconds, but traditional search strategy 450 milliseconds (ms) have but been spent, unit method for searching (RSPT) to the second embodiment of the present invention has but been spent 380 milliseconds (ms), the unit method for searching (RSPF) of the third embodiment of the present invention has but been spent surpass 600 milliseconds (ms).
Figure 14 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 8KHz, compare the performance plot of different units method for searching.Under this situation, at a duration of test, sampling frequency deviation almost reach the chip time half.If at the end of phase III, sampling frequency deviation is bigger than the chip time, then this test success never.As shown in the figure, the unit method for searching (RSPT) of the second embodiment of the present invention has important improvement with the unit method for searching (RSPF) of the third embodiment of the present invention compared with conventional method.This is because under the appearance of sampling frequency deviation, grab sample has preferable chance and removes to obtain more rational sampling point in three phases.
Figure 15 is for to have imperfect sampling effect and sampling frequency deviation effect f
ΔUnder=the 12KHz, compare the performance plot of different units method for searching.Along with the increase of sampling frequency deviation, it is bigger that the difference of the operating characteristic of the unit method for searching (RSPF) of the unit method for searching (STS1) of the traditional approach and the first embodiment of the present invention, the unit method for searching (RSPT) of the second embodiment of the present invention and the third embodiment of the present invention becomes.Know that by Figure 14 and Figure 15 in sampling frequency deviation situation following time, the unit method for searching (RSPF) of the third embodiment of the present invention is preferable selection.
Therefore, be used for this unit method for searching of demal multitask access system according to the present invention, the effect that can reduce frequency shift (FS) effectively and caused at this demal multitask access system and reach initial synchronisation fast.
This unit search device that is used for demal multitask access system according to the present invention can be realized the unit search device and not increase the complexity of hardware at sampling frequency deviation effect that frequency shift (FS) caused.The method according to this invention and device can be used for running gear and radio individual digitlization assistant (PDA) system.
Though the present invention explains with regard to embodiment, know that by above-mentioned most corrections can be implemented and can not break away from the original purpose spirit of this creation and the idea of innovation with changing.Need be appreciated that shown certain specific embodiments is not intention or means in order to restriction the present invention; The intention that is proposed comprises the field that the claim that added and all corrections will fall into the Patent right requirement scope.
Claims (32)
1. a unit method for searching is used for demal multitask access system, it is characterized by: use the unit search process of three phases in this method, this method comprises the following step:
Coupling (match) is from an entering signal of base station;
This entering signal is crossed sampling N time and exported N sampling point (Y of sampling with a spreading rate
1(k), Y
2(k) ... Y
N(k));
This entering signal is fallen sampling and exported this N sampling point to N bar parallel signal path;
Cross sampling point with this N and do phase I processing in regular turn, a second stage is handled and a phase III handles to finish a test (trial);
Wherein, cross sampling point for this N and handle, in this second stage processing and the processing of this phase III different uses is arranged in this phase I by a control procedure.
2. unit as claimed in claim 1 method for searching is characterized by: this test of this unit search also comprises the following step:
In the phase I processing, a time slot that can obtain this entering signal is synchronous;
In second stage is handled, detect a code group and the frame synchronization of this entering signal;
In the phase III processing, select a disturbing code of this entering signal;
Test this disturbing code and a hurdle value η
0Do one first authentication;
If wherein this hurdle value is not exceeded, then this test writes off, and a new test will restart under not postponing; Otherwise
Selected this disturbing code carries out one second checking;
If wherein this disturbing code is by this second checking, then success of the test, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).
3. unit as claimed in claim 1 method for searching is characterized by: this control procedure also comprises the following step:
In the phase I processing, choose an optimal sampling point in the sampling point excessively at this N.
4. unit as claimed in claim 3 method for searching is characterized by: this optimal sampling point that this N crosses in the sampling point is not being disturbed under the appearance, is to cross at this N to have maximum sampling value in the sampling point.
5. unit as claimed in claim 1 method for searching is characterized by: this control procedure also comprises the following step:
In the phase I processing, choose a sampling point randomly in the sampling point excessively at this N, and be sent to second stage processing and phase III processing, to carry out three phase process in this test.
6. unit as claimed in claim 1 method for searching is characterized by: this control procedure also comprises the following step:
When handling, cross in the sampling point at this N at random and independently and choose a sampling point, in each stage of this test, to handle in phase I processing, second stage processing and phase III.
7. unit as claimed in claim 2 method for searching is characterized by: this phase I handles and also comprises the following step:
In an elementary synchronizing channel, the Ge Lei sequence (generalizedhierarchical Golay sequence) of using vague generalization class system is as an elementary synchronous code.
8. unit as claimed in claim 2 method for searching is characterized by: this second stage is handled and is also comprised the following step:
In level synchronizing channel, use 16 secondary synchronization sign indicating numbers, wherein this secondary synchronization sign indicating number and this elementary synchronous code quadrature.
9. unit as claimed in claim 8 method for searching, it is characterized by: this secondary synchronization channel is by using one (15,3) free of discontinuities Reed Solomon code (comma-free Reed Solomoncode, CFRS), further be encoded into one group of 64 code word, wherein each code word that should organize is by telogenesis one code group, in order to identification one frame border and code group.
10. unit as claimed in claim 2 method for searching is characterized by: this phase III handles and also comprises the following step:
After this code group was by identification, this disturbing code can select one in 8 code words to decide via a common pilot channel.
11. unit as claimed in claim 7 method for searching is characterized by: select to surpass the candidate (candidate) of more than one time slot border as a preferable operation in this elementary synchronous code, trough rim circle is correct though only have for the moment.
12. unit as claimed in claim 9 method for searching is characterized by: this frame boundaries and the code group handled in second stage are the maximum of the shift position of this code group and this circulation.
13. unit as claimed in claim 2 method for searching is characterized by: this hurdle value η
0(constant false alarm rate) decides according to the fixed error alarm rate.
14. unit as claimed in claim 1 method for searching is characterized by: this unit method for searching is used in the wide band code division multitask and accesses/Frequency Division Duplexing system.
15. unit as claimed in claim 1 method for searching is characterized by: this unit method for searching is used in running gear and radio individual digitlization assistant (PDA) system.
16. a unit search device is used for demal multitask access system, it is characterized by: this device is realized the unit search of three phases, and this unit search device comprises:
One chip matched filter is in order to the entering signal of coupling from base station;
One sampling assemble is linked to this chip matched filter, in order to this entering signal is crossed sampling N time and exported N sampling point (Y of sampling with a spreading rate
1(k), Y
2(k) ... Y
N(k));
One falls sampler, is linked to this sampling assemble, crosses and to get o'clock to a phase I detector, a second stage detector and a phase III detector in order to export this N;
This phase I detector is connected in this and falls sampler, be used to obtain this entering signal a time slot synchronous;
This second stage detector is linked to this and falls sampler, in order to obtain a code group and the frame synchronization of this entering signal;
This phase III detector is linked to this and falls sampler, in order to determine a disturbing code of this entering signal;
One control assembly, be linked to this phase I detector, this second stage detector and this phase III detector, in this phase I detector, this second stage detector and this phase III detector, do different uses in order to control this N mistake sampling point; And
One authentication ' unit is linked to this phase III detector, is used to determine whether this test is successful.
17. unit as claimed in claim 16 search device is characterized by: this authentication ' unit also comprises:
One comparator is linked to this phase III detector, in order to test output this disturbing code and hurdle value η from this phase III
0Relatively;
Whether one first decision assembly is connected to this comparator, correct in order to determine this disturbing code;
If wherein this hurdle value is not exceeded, then this test writes off, and a new test will restart under not postponing, and anti-, if this hurdle value is exceeded, this disturbing code that is then determined promptly enters together step card unit;
The unit of checking synchronously is linked to this first decision assembly, in order to verify this disturbing code; And
Whether one second decision assembly is connected to this unit of checking synchronously, accept in order to determine this disturbing code;
If wherein this disturbing code is by this second decision assembly, then success of the test, otherwise a new test one time of delay T
PRestart behind the millisecond (ms).
18. unit as claimed in claim 16 search device is characterized by: this phase I detector is chosen an optimal sampling point in the sampling point by the control of this control assembly excessively at this N.
19. unit as claimed in claim 18 search device is characterized by: this optimal sampling point is not being disturbed under the appearance, is to cross at this N to have maximum sampling value in the sampling point.
20. unit as claimed in claim 16 search device, it is characterized by: this phase I detector is by the control of this control assembly, choose a sampling point randomly in the sampling point excessively at this N, and be orderly sent to this second stage detector and this phase III detector, to proceed this triphasic unit search.
21. unit as claimed in claim 1 search device, it is characterized by: by the control of this control assembly, this phase I detector, this second stage detector and this phase III detector, cross in the sampling point at this N at random and independently and choose a sampling point, in each phase detector, to handle.
22. unit as claimed in claim 16 search device, it is characterized by: this first detector uses the hierachical Ge Lei sequence of vague generalization (generalizedhierarchical Golay sequence) as an elementary synchronous code in an elementary synchronizing channel.
23. unit as claimed in claim 16 search device is characterized by: this second detector uses 16 secondary synchronization sign indicating numbers in level synchronizing channel, wherein this secondary synchronization sign indicating number and this elementary synchronous code quadrature.
24. unit as claimed in claim 23 search device, it is characterized by: this secondary synchronization channel is by using one (15,3) free of discontinuities Reed Solomon code (comma-free Reed Solomoncode, CFRS), further be encoded into one group of 64 code word, wherein each code word that should organize is by telogenesis one code group, in order to identification one frame border and code group.
25. unit as claimed in claim 16 search device is characterized by: after this code group was by identification, this disturbing code can select one of 8 code words to decide via a common pilot channel.
26. unit as claimed in claim 16 search device is characterized by: this phase I detector uses a non-matched filter execution time slot that is mixed into together synchronous.
27. unit as claimed in claim 22 search device is characterized by: this phase I detector selects to surpass the candidate of more than one time slot border as a preferable operation in this elementary synchronous code, though only there is a candidate to be taken into account.
28. unit as claimed in claim 23 search device is characterized by: this second stage detector uses 16 matched filters to detect this secondary synchronization sign indicating number.
29. unit as claimed in claim 24 search device is characterized by: this second stage detector detects the maximum of shift position of this code group and this circulation with as this code group and frame boundaries.
30. unit as claimed in claim 17 search device is characterized by: this hurdle value η
0Decide according to the fixed error alarm rate.
31. unit as claimed in claim 17 search device is characterized by: this unit search device is used in the wide band code division multitask and accesses/Frequency Division Duplexing system.
32. unit as claimed in claim 17 search device is characterized by: this unit search device is used in running gear and radio individual digitlization assistant pda system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN02120154A CN1459944A (en) | 2002-05-21 | 2002-05-21 | Unit searching mode and device used for wide band code division multi job access system and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN02120154A CN1459944A (en) | 2002-05-21 | 2002-05-21 | Unit searching mode and device used for wide band code division multi job access system and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1459944A true CN1459944A (en) | 2003-12-03 |
Family
ID=29426952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN02120154A Pending CN1459944A (en) | 2002-05-21 | 2002-05-21 | Unit searching mode and device used for wide band code division multi job access system and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1459944A (en) |
-
2002
- 2002-05-21 CN CN02120154A patent/CN1459944A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6813478B2 (en) | Method and apparatus for searching a gated pilot | |
| CN1135767C (en) | Method and apparatus for acquiring pilot signalin CDMA receiver | |
| JP4667784B2 (en) | Method for displaying group codes belonging to a base station of a time division duplex (TDD) communication system | |
| CN1157006C (en) | CDMA mobile communication equipment and base station test method thereof | |
| US20030202564A1 (en) | Method and apparatus for cell search for W-CDMA with effect of clock offset | |
| CN1659795A (en) | Method and apparatus for improved cell detection | |
| CN1120591C (en) | Direct bandspread/comprehensive CDMA bandspread coherent receiver | |
| CN1138368C (en) | Apparatus and method of searching for PN sequence phase in multi-carrier CDMA mobile communication system | |
| US7173958B2 (en) | Method for cell search under effect of high clock offset | |
| CN1210879C (en) | Pilot signal search method with decimation reordering in CDMA system | |
| CN101103547A (en) | Cell search using Rake searcher to perform scrambling code determination | |
| CN1133351C (en) | Time slot synchronizer in regional search for WCDMA system | |
| CN1820437A (en) | Frequency synchronization during cell searching in universal mobile telephone system receiver | |
| CN1224203C (en) | Method and apparatus for wideband CDMA and cell searching with non-ideal sampling effect | |
| CN1468471A (en) | Searching for signals in a communications system | |
| CN1510858A (en) | Apparatus and method for identifying mobile signal in mobile communication system | |
| CN1459944A (en) | Unit searching mode and device used for wide band code division multi job access system and device | |
| CN1794602A (en) | Receiving equipment, receiving method and program thereof | |
| CN1588834A (en) | Frequency deviation evaluation device and method | |
| CN1243418C (en) | Honeycomb searching method under high sampling frequency deviation effect | |
| CN1459943A (en) | Unit searchig method used for W-CDMA and device | |
| CN1228929C (en) | Parameter driving controlled honeycomb searching device | |
| CN1595834A (en) | Method and apparatus for initial synchronization in CDMA mobile communication system | |
| CN1627835A (en) | Method for testing modulated phase cluster of sync code in time division synchronization CDMA access system | |
| CN1247442A (en) | Sequential path searching method among mobile communicating system transmitted under variable data speed |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |