CN1281602A - Method and receiving device for estimating channels in communications systems - Google Patents
Method and receiving device for estimating channels in communications systems Download PDFInfo
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- CN1281602A CN1281602A CN98812173.5A CN98812173A CN1281602A CN 1281602 A CN1281602 A CN 1281602A CN 98812173 A CN98812173 A CN 98812173A CN 1281602 A CN1281602 A CN 1281602A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0224—Channel estimation using sounding signals
- H04L25/0228—Channel estimation using sounding signals with direct estimation from sounding signals
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0212—Channel estimation of impulse response
Abstract
According to the invention, a receive signal consisting of data symbols is received by a receiving station. Said receive signal is split up into individual sampling values at the receive end and compared with known data symbols in order to determine channel coefficients, individual known data symbols of the receive signal being stored in the receive station. Since less channel coefficients are determined for fast-moving mobile stations, the estimation accuracy for these channel coefficients improves.
Description
The present invention relates in having the communication system of transmission channel between radio station, wherein at least one moves, and is used for the method and the receiving system of channel estimating.
Message in radio communications system (for example language, pictorial information or other data) is the process transmission channel, and this carries out through radio interface by means of electromagnetic wave in radio-communication system.Electromagnetic emission this moment is carried out with carrier frequency, and carrier frequency is to be on the frequency band of each system arrangement.The frequency domain of carrier frequency is 900MHz in GSM (global system for mobile communications).For the radio-communication system in future, for example UMTS (omnipotent mobile radio communicaltions system) or other the 3rd generation system frequency arrangement is being approximately on the frequency band of 2000MHz.
The electromagnetic wave that is launched is owing to the loss and the similar reason of reflection, diffusion and earth curvature emission are subjected to damping.Therefore reduced received power, this received power is to provide use on the radio station that receives.This damping is relevant with the position and relevant with the time on mobile radio station.It is faster that mobile radio station moves, and then the channel condition of transmission channel also has very big variation in the short time interval.Different delays appears in multiple signal component on the radio station that receives in multipath propagation.The influence of being narrated has been described and has been communicated to connect single transmission channel.
Known a kind of radio-communication system from DE 195 49 148, this radio-communication system have been utilized CDMA-user classification method (CDMA code division multiple access), and wherein radio interface adds time division multiple access-user classification method (TDMA-time division multiple access).Use a kind of JD-detection method (joint-detection) the recipient, know with box lunch and improve the detection that is transmitted data under a plurality of users' the CDMA-coding situation.Known therein, can distribute to one through at least two data channels of radio interface and communicate to connect, wherein each data channel can be distinguished by independent extended coding.
Known from the GSM-mobile radio communication network, the data that are transmitted are transmitted in time slot as radio blocks (pulse train), and wherein that the radio station of mid portion in the radio blocks and reception is known symbol transmits.This mid portion can be utilized as the meaning of learning sequence coordinate radio station the recipient.The radio station that receives carries out channel estimating by means of mid portion, that is to say for the channel impulse response of different transmission channels and assesses.Selectively can put in order by the channel of dissimilar CDMA-coding name abreast for learning sequence and useful data.
When changes in channel conditions was very fast, the channel impulse response of transmission channel also changed in the radio blocks that is transmitted, and so only the part with radio blocks is used for channel estimating.Irrespectively determine a fixing quantity of equidistant channel coefficients with channel condition.Yet this channel estimating is inaccurate.
Task of the present invention is that a kind of method and a kind of receiving system of predetermined channel assessment are though very fast these method and apparatus that move of mobile radio station can be determined channel coefficients reliably.This task is to solve by method with claim 1 feature and the receiving system with claim 11 feature.The favourable expansion structure of the present invention can be learned from dependent claims.
Be used for the method for channel estimating according to the present invention between the radio station of the communication system with transmission channel, wherein at least one radio station moves, and receives the received signal that is made of data symbol from receiving station.Wherein data symbol changes by a kind of transmission method, for example by expansion, modulation and channel distortions.
Received signal is resolved into single scan values the recipient, and in order to determine that channel coefficients and known data symbol compare, wherein the data symbol of single known received signal is stored in receiving station.Thereby, only determine the quantity of the channel coefficients that reduces for very fast mobile mobile radio station, improved the assessment precision for these channel coefficients.Eliminate the wrong ratio of sub-block and long desired channel impulse response of the weak point of received signal, and improved the precision of evaluated channel impulse response.When the slow quantity of determining many channel coefficients when mobile of mobile radio station.
Also can cancel restriction by this channel estimating mode, not need to prolong simultaneously learning sequence or reduce data transfer rate the channel condition of the restriction of radio station speed and permission.The present invention not only can use in the transmission between base station and the mobile radio station, and can use in the transmission between the mobile radio station.
According to the favourable structure of the present invention, known data symbol with scan values and the data symbol in the learning sequence that is sent out are compared, perhaps known data symbol is stored after Data Detection, and compared with the scan values of original reception subsequently.So or can turn back to the not known data symbol of distortion, the data transfer rate that this data symbol sacrifice is very little allows channel estimating more accurately.The accurate data assessment is a prerequisite of deriving channel coefficients continuously in second kind of modification.Therefore can during handling a part of radio blocks that does not comprise learning sequence, improve channel estimating.
Other characteristics of the present invention have been arranged, and have considered to reduce the quantity of the numerical value of given data symbol when determining channel coefficients, that is to say learning sequence or evaluated data symbol.Therefore in the time interval that shortens, also obtain accurately assessed value with the channel coefficients of reality for the scan values of preparing to handle.
In addition advantageously, the channel coefficients of preparing to determine is selected like this, and the power averaging of these channel coefficients is stronger than there not being selected numerical value.Therefore guaranteed, still can enough describe transmission channel exactly, and the data assessment as the back constitutes the basis of getting well under the channel coefficients situation using though reduced the quantity of channel coefficients.For example chosen numerical value can take out from the quantity of definite before this bigger channel coefficients.From the channel estimating of front therefore according to the present invention only with the reprocessing of far reaching channel coefficients.The selected channel coefficients of preparing to determine is carried out repetition with bigger distance, so as with respect to single be not the development of the meaning of the channel coefficients of calculating continuously.
According to the favourable expansion structure of the present invention, the distance of the numerical value of chosen channel coefficients is not equidistant.Therefore also can represent now to be the big temporal extension of channel impulse response (by the multipath propagation decision) corresponding to the single channel impulse response of different transmission channels, if the channel coefficients when channel impulse response begun and finish is chosen to be far reaching.Unnecessary consideration this moment is equidistant.
The quantity of the numerical value by reducing certain channel coefficients has constituted an equation e=Gh+n who crosses the location, and wherein G is that piece sequential matrix and n are noise sections.Owing to cross the precision that channel estimating has been improved in the location.Wherein the precision of Que Dinging can with the weighing of reality.Be favourable equally, the quantity of the scan values that is considered when channel estimating can depend on the channel condition of transmission channel and reduce.Therefore reduced and crossed the location, yet that channel estimating becomes is more real.
In addition advantageously, the consideration of the signal delay time of reasonable length makes elongated based on the distance between the channel coefficients of signal delay time, need not increase the quantity of channel coefficients with same yardstick.Therefore channel impulse response also can be considered special channel condition (for example at the place, straits) though with seldom scan values also enough channel estimatings.
Be described in detail embodiments of the invention by means of accompanying drawing.
Wherein expression
The block diagram of accompanying drawing 1 mobile radio communication network,
The sketch of accompanying drawing 2 radio interface frame structures,
The sketch of accompanying drawing 3 radio blocks,
The block diagram of accompanying drawing 4 radio station receivers,
The block diagram of accompanying drawing 5 digital signal processing devices,
The block diagram of accompanying drawing 6 channel estimating problems and
The procedure chart of accompanying drawing 7 channel estimatings.
The radio-communication system of expression on the accompanying drawing 1 on its structure corresponding to known GSM-mobile radio communication network, this is made up of the mobile exchange station MSC that much constitute network mutually, and has set up inlet with fixed network PSTN.These mobile exchange stations MSC links to each other with at least one base station monitoring device BSC separately in addition.Each base station monitoring device BSC might establish a communications link with at least one base station BS again.Such base station BS is a radio station, and this can set up dedicated radio link with mobile radio station MS through radio interface.
On accompanying drawing 1 example shown three dedicated radio link V1 ... V3 is used for transmission useful information ni and signaling information si between three mobile radio station MS and base station BS, and the mobile radio station of distributing to two data channel DK1 of a mobile radio station MS and DK2 this moment and distributing to other is data channel DK3 and DK4 separately.Operation-and the OMC of maintenance centre realize monitoring-and maintenance function for mobile radio communication network and parts thereof.The functional of this structure utilized by radio-communication system according to the present invention; This functional also can transferring in other radio-communication system also can be used the present invention thereon.
Base station BS links to each other with the antenna assembly of being made up of three single reflectors.Each single reflector is aimed at by a zone of the radio plot of base station BS supply and is launched.Yet also can select to use many single reflectors (according to the antenna of coupling), so also can use space customer separating method according to SDMA-method (space division multiple access).
Communicating to connect of useful information ni between base station BS and the mobile radio station MS and signaling information si is in multipath propagation, and multipath propagation for example is to be attached on the direct transmission path by the reflection on the building to cause.Therefore the signal component of same subscriber signal that is subordinated to different propagation paths on different time points, meet (delay transit) in receiving station.
People are mobile from mobile radio station MS's, and then multipath propagation and other interference cause jointly, and the signal component on the different propagation paths of a subscriber signal on the mobile radio station MS that receives overlaped with the time relevantly.In addition from here, the subscriber signal of different base station BS locally overlappingly on a channel becomes a received signal rx receiving.The task of the mobile radio station MS that receives is, the subscriber signal transmission channel is carried out channel estimating, channel estimating is very fast at mobile radio station MS also to be enough accurate and real when mobile, and the data symbol of the useful information ni that transmits in subscriber signal, the data symbol of signaling information si and the data of management information detect.
From accompanying drawing 2, see the frame structure of radio interface.Forming according to TDMA-is the distribution of broadband frequency domain, and for example bandwidth is that B=1.6MHz is arranged on a plurality of time slot ts, for example 8 time slot ts1 to ts8.Each time slot ts in the frequency domain B constitutes a channel.In the channel that is used for the transmitting useful data arrangement, a plurality of information that communicate to connect are transmitted with radio blocks.Distribute to a plurality of frequency domain B of radio-communication system according to FDMA (frequency division multiple access)-composition.
The radio blocks that is used for useful data transmission according to accompanying drawing 3 is made up of the data division dt with data symbol d, inserts the known mid portion m of recipient in the data portion segmentation.Data d is with communicating to connect the expansion of independent fine structure, an extended coding (CDMA coding), and recipient K data channel DK1 for example like this, DK2, DK3 ... DKK can separate by this CDMA-composition.Transmit leg is given each data channel DK1 with each allocation of symbols, DK2, and DK3 ... DKK certain energy E.
The single symbol of data d transmits with Q piece expansion, the son section Q with period T c in symbol period Ts.Wherein the Q piece constitutes independent CDMA-coding.Mid portion m with learning sequence tseq is that L the piece of Tc formed by the same cycle.The cycle of having arranged is that the guard time guard of Tg is used to compensate communicating to connect of continuous slot ts different signal running time in this external time slot ts.
Continuous slot ts divides into groups according to frame structure in broadband frequency domain B.Like this eight time slot ts are comprehensively become a frame, this moment certain time slot of frame is constituted and be used for the useful data channel transmitted, and a group of returning and being communicated to connect is utilized.Other channel for example is used for the frequency-synchronized of mobile radio station MS or time synchronizedization not in each frame, but is inserted on the time point of predesignating in the multiframe.
For example the parameter of radio interface is as follows:
The cycles 577 μ s of radio blocks
The piece of each mid portion m several 243
Guard time Tg 32 μ s
The data symbol 33 of each data division N
Symbol period Ts 6.46 μ s
The piece of each symbol Q several 14
At up direction (MS-＞BS) and down direction (BS-＞MS) can carry out different adjustment to parameter.
Recipient according to accompanying drawing 4 relates to radio station, and this not only can be base station BS but also can be mobile radio station MS.Be used for channel estimating the recipient according to receiving system of the present invention.Corresponding reflector in the cards for example can be learned from Germany Patent document DE 197 34 936.
On accompanying drawing 4, be described in detail the RX path of device.In submodule E1, received signal rx is become the low pass scope from sending frequency band conversion, and be divided into a reality and a composition void.On submodule E2, carry out analogue low pass filtering, and will to have 13/3MHz and word subsequently wide on submodule E3 be that the received signal of 12 bits is carried out two times overscanning.
Dedicated bandwidth is that the filter that 13/6MHz has a channel separation of high as far as possible profile slope carries out digital filtering on submodule E4.Last on submodule E4, the signal of twice overscanning carried out 2: 1 1/10th change.
The received signal e that obtains so mainly is made up of two parts, promptly forms by the part em that is used for channel estimating (the learning sequence tseq with given data symbol t) with by part e1 that is used for data assessment and e2.In submodule E5, carry out the channel coefficients h of channel impulse response by means of the known mid portion basic coding m of the data channel that transmits in all each comfortable time slots
(k)Assessment.
In submodule E6, use CDMA-coding c
(k)Determine the parameter b of the filter that each data channel is mated
(k)Will be in submodule E7 by mid portion m
(k)The interference that causes is restricted to minimum at the reception data block e1/2 that is used for the data assessment use.This is owing to know h
(k)And m
(k)Possible.
In submodule E8 to E12 by means of puppet-transposition specified data symbol d of comprehensive channel matrix A.Other solution is with the singular value decomposition of comprehensive channel matrix A (decomposition of odd number value).Other solution relates to other optimality criterion, and for example least mean-square error criterion (MMSE) replaces zero-g (ZF) criterion.In addition also might anti-coupled structure.These solutions also can make up mutually.
In submodule E8, carry out cross-correlation A
* TThe computing of A.Because A
* TA has a Toeplitz-structure, only needs the sub-fraction of operation matrix here, this can be expanded using whole matrix.When movable part is slowly mobile, this matrix A
* TA is big, because people select big sub-block.A in this matrix
* TA computing sub-fraction among the A.Matrix A when more mobile than faster
* TA diminishes, and then people select whole computing sometimes, so that reach low noise result.In submodule E9 with A
* TA carries out Cholesky-and is decomposed into H
* TH, wherein H is a upper triangular matrix.Because A
* TA is the Toeplitz-structure, and H also is the Toeplitz-structure approx and does not need whole computing.Vector s represents the inverse of H quadrature unit, can advantageously use in the formula operation device.
In submodule E10 with receiving symbol order e1/2 and b
(k)Carry out matched filtering (matched filter).Submodule 11 is realized H
* T* the formula group decomposer 1 of z1/2=e1/2.In submodule E13, evaluated data d1/2 is carried out demodulation, separate cube and separate encoder with Viterbi-subsequently and roll up the collected explanations or commentaries sign indicating number.With decoded data block e
(k)E13 inputs to first data remittance D1 selectively or inputs to second data remittance D2 through source decoder E14.Additionally with decoded data block e
(k)E13 returns and inputs to submodule E5, and submodule E5 utilizes these data blocks to follow the tracks of evaluated channel coefficients h.
Recipient's (seeing accompanying drawing 5) that is to say that amplification, filtering, convergence become the base band in the HF-part, carry out digital filtering with received signal rx in wave digital lowpass filter after simulation process.With the part of digitlization received signal e, this is to be interference vector em representative and that do not comprise data division dt of L=M*W by length, is transferred to the processing unit of the numeral that comprises channel estimator KS.In joint-detection data assessment device, all are communicated to connect and carry out data assessment jointly, wherein can from Germany Patent document DE 197 34 936, learn detailed narration.
Be described in detail the channel estimating in submodule E5 below.Submodule E5 comprises a channel estimator KS, a storage device SP and a control device SE, can exchange message between these.In storage device SP, stored the data symbol t of learning sequence tseq known from middle part m, and the detected data symbol d that follows the tracks of assessment.Control device SE can the user change between the various patterns of channel estimating individually, carries out channel estimating this moment in channel estimator KS.By means of the scan values e1 of channel estimating from received signal e ... determine channel coefficients h among the e16.
In accompanying drawing 6, represented the channel estimating problem.The data symbol d that is sent out is changed by transmission method, and the channel matrix A by combination represents and occurs as scan values e on the radio station that receives.When channel estimating is determined the channel matrix A of evaluated combination, receive radio station and attempt to determine assessed value d for the data symbol d that is sent out.For example the optimization criterion is scan values e and the Minimum Mean Square Error of preparing the received signal e of assessment.When from learning sequence tseq, carrying out channel estimating d=t and when following the tracks of evaluated d return coupling and d=d.
In mobile radio system, carry out channel estimating and must consider moving of mobile radio station MS.Move and to cause Doppler-move, the amplitude that this can be by individual channel parameter h (a1 complex values)-be described with phase change is seen the channel model among the Germany Patent document DE 196 35 271.If a lot of channel coefficients h use same distance, the numerical value change of individual channel coefficient h, however the maintenance of the profile of channel impulse response is constant.Therefore can during a radio blocks, also can carry out channel estimating continuously with following the tracks of channel coefficients h for the mobile radio station MS that compares fast moving by handling detected data symbol d.
When mobile at a slow speed the numerical value of channel coefficients h be based upon based on mid portion m on the mean value basis of a plurality of radio blocks upper signal channels assessments.If under the frequency tight situation, only consider the radio blocks of same carrier frequency.Mid portion is compressed and follows the tracks of channel coefficients and also carries out outside the mid portion m that is made of learning sequence tseq than fair speed the time when average speed.The conversion of channel estimating pattern be on receiving system by control device SE and assessment precision, setting aside some time accordingly running time with the pace of change of measured channel impulse response or with signal, the pace of change of (time is in advance) carries out relevantly.
For the data division of following the tracks of radio blocks is divided into sub-block, can suppose that like this channel condition does not have obvious variation when sub-block.Channel coefficients h that Data Detection use front is determined and the given data symbol d (e13 in accompanying drawing 4) that sub-block is detected return and are used for channel estimating.Can sub-block is overlapping for the delay minimization that makes channel estimating, so for example first sub-block comprises data symbol 1 to 10, and second sub-block comprises data symbol 2 to 11 etc.
Problem occurs in the short sub-block with given data symbol d, and the ratio of the quantity that a lot of long channel impulse responses and given data symbol t are restricted in mid portion m on learning sequence tseq basis.Strive for using a formula group of location excessively in order enough to constitute channel estimating exactly.
Channel estimating (step 1) is handled received signal relevant with the time during learning sequence tseq in the accompanying drawing 7:
Wherein n (t) is as noise section and the x symbol as the volume set operation.Can be rewritten as with this formula of matrix literary style, e=Ad+n, wherein Zu He channel matrix A has reacted the influence of expanding by CDMA-coding c and has reacted by the modulation of transmission channel with the channel coefficients h for preparing assessment.
This Matrix Formula is found the solution (step 2 in accompanying drawing 7) with the least square method solution:
A wherein
+As matrix A, the comprehensive transposition of A ' is as sealing the vector (^ represents assessed value) that matrix A and d are transformed as data symbol d.
Carry out after the data assessment, if when very fast mobile mobile radio station MS (be necessary that in order to follow the tracks of channel coefficients h the sub-block that includes with section data among the e to received signal recomputates in accompanying drawing 7 step 3):
Piece order g and its matrix literary style of wherein c and h comprehensively being become combination are: e=Gh+n, then channel coefficients h by means of
Assess (the step 6) of accompanying drawing 7.
A lot of transmission channels can enough be described exactly with the weak channel coefficients h of relative power, and these channel coefficients distribute on the big time gap of signal delay decision sometimes.
The delay (position) of these far reaching channel coefficients h (is seen accompanying drawing 7) on step 4 decision.The quantity of the channel coefficients h that when the processing of the sub-block of back, has only determined to have reduced then.
For example for the scan values e1 for preparing to find the solution with three subscriber signal A, B, C and 16 received signal e ... the formula group of e16 has following form:
It was the assessment result location and that cause having noise jamming that this formula group is easy to.The vector of piece sequential matrix G and channel coefficients h is to draw dotted line, then only keeps far reaching channel coefficients h.
If will add the element deletion of dotted line, then draw the formula group of shortening:
This formula group is very consistent with the quantity that reduces channel coefficients h=hs, then according to formula
(accompanying drawing 7 step 5) improve to make the precision of assessment.
This program also can be used on the signal delay that can represent by the expansion channel impulse response.The quantity of channel coefficients h remains unchanged, yet it is apart from having enlarged.
Claims (15)
1. the method for channel estimating in the communication system between base station (BS) and mobile radio station (MS) with transmission channel, wherein not only base station (BS) but also mobile radio station (MS) can send and receive,
Therein,
-receiving station (MS BS) go up to receive the received signal (e) that includes the data symbol that is changed by transmission method,
-the recipient received signal (e) is decomposed into single scan values (e1 ... e16),
-receiving station (MS, BS) go up storage received signal (e) single known data symbol (d, t),
-in order to determine that channel coefficients (h) is with scan values (e1 ... e16) and known data symbol (d t) compares,
-wherein determine to reduce the channel coefficients (h) of quantity for moving fast mobile radio station (MS).
2. according to the method for claim 1, therein, with the scan values (e1 of known data symbol (t) with data symbol ... e16) on the training sequence that is sent out (tseq), compare.
3. according to the method for claim 1, therein, (d) stores after Data Detection with known data symbol, and with the scan values (e1 of original reception ... e16) compare.
4. the method that one of requires according to aforesaid right therein, will be considered the quantity of minimizing of the numerical value of piece sequential matrix (Gs) when determining channel coefficients.
5. according to the method for claim 4, therein, the digital average that selected channel coefficient (h) is reduced quantity is better than on power does not have chosen numerical value.
6. according to the method for claim 5, therein, chosen numerical value is to take out from the bigger quantity of the channel coefficients of determining before this (h).
7. according to the method for one of aforesaid right requirement, therein, the distance of the chosen numerical value of the piece sequential matrix (Gs) that is reduced is not equidistant.
8. the method that one of requires according to aforesaid right, therein, the quantity of the channel coefficients (h) that is determined by minimizing has proposed the formula group e=Gh+n that very consistent preparation is found the solution, and wherein n is that noise section and G are the piece sequential matrix.
9. the method that one of requires according to aforesaid right, therein, the scan values (e1 that when channel estimating, considers ... e16) quantity depends on the channel condition of transmission channel and reduces.
10. the method that one of requires according to aforesaid right, therein, the distance between channel coefficients (h) on the signal delay time basis becomes big, does not need the quantity of channel coefficients (h) is amplified with same yardstick.
11. the receiving system of communication system,
Have a storage device (SP) and be used to store the scan values (e1 of received signal (e) ... e16), received signal comprises the data symbol that is changed by transmission method, and be used to store received signal (e) known data symbol (d, t) and
Have a channel estimator (KS) and be used for channel estimating transmission channel,
-wherein in order to determine that channel coefficients (h) is with scan values (e1 ... e16) with known data symbol (d, t) compare and
-wherein determine the minimizing quantity of channel coefficients (h) for moving fast mobile radio station (MS).
12. according to the receiving system of claim 11, therein, the chosen digital average of the minimizing quantity of channel coefficients (h) is better than on power does not have chosen numerical value.
13. according to the receiving system of claim 11 or 12, therein,
Scan values (the e1 that when channel estimating, considers ... e16) quantity depends on the channel condition of transmission channel and reduces.
14. according to the receiving system of one of claim 11 to 13, therein,
With a plurality of subscriber signals during through different transmission channel, it is a received signal (e) that these transmission channels are gone up overlapping at receiving system (EE) subscriber signal on a channel.
15. according to the receiving system of one of claim 11 to 14, therein,
The learning sequence (tseq) that will comprise given data symbol (t) transmits on identical channel with subscriber signal.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19745367.8 | 1997-10-14 | ||
| DE19745367 | 1997-10-14 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1281602A true CN1281602A (en) | 2001-01-24 |
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ID=7845516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN98812173.5A Pending CN1281602A (en) | 1997-10-14 | 1998-09-29 | Method and receiving device for estimating channels in communications systems |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP1023784A2 (en) |
| JP (1) | JP2001520492A (en) |
| CN (1) | CN1281602A (en) |
| AU (1) | AU1143599A (en) |
| WO (1) | WO1999020061A2 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19935480A1 (en) | 1999-07-28 | 2001-02-22 | Infineon Technologies Ag | Method for estimating the channel impulse responses of a mobile radio channel |
| DE19938747A1 (en) * | 1999-08-16 | 2001-03-22 | Siemens Ag | Method for channel estimation in a radio communication system |
| EP1091533B1 (en) * | 1999-10-07 | 2006-10-04 | Robert Bosch Gmbh | A method and device for channel estimation in a mobile communication system, particularly in a mobile phone |
| TW540200B (en) | 2000-11-09 | 2003-07-01 | Interdigital Tech Corp | Single user detection |
| US7593357B2 (en) | 2002-03-28 | 2009-09-22 | Interdigital Technology Corporation | Transmit processing using receiver functions |
| US20050232340A1 (en) * | 2004-04-16 | 2005-10-20 | Lucent Technologies, Inc. | Intelligent antenna receiver architecture |
| WO2006106474A2 (en) * | 2005-04-08 | 2006-10-12 | Koninklijke Philips Electronics N.V. | Method and apparatus for estimating channel in mobile communication system |
| EP1985080A2 (en) * | 2005-12-20 | 2008-10-29 | Koninklijke Philips Electronics N.V. | A method for signal reception in a ofdm system |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2953132B2 (en) * | 1991-09-12 | 1999-09-27 | 松下電器産業株式会社 | Data receiver equalizer |
| JP2770626B2 (en) * | 1991-11-29 | 1998-07-02 | 日本電気株式会社 | Adaptive receiver |
| FR2698226B1 (en) * | 1992-11-18 | 1995-01-13 | Alcatel Radiotelephone | Learning sequence for the estimation of a transmission channel and corresponding estimation device. |
| FI98018C (en) * | 1994-08-18 | 1997-03-25 | Nokia Mobile Phones Ltd | Method and apparatus for measuring the impulse response of a radio channel |
-
1998
- 1998-09-29 CN CN98812173.5A patent/CN1281602A/en active Pending
- 1998-09-29 WO PCT/DE1998/002873 patent/WO1999020061A2/en not_active Application Discontinuation
- 1998-09-29 AU AU11435/99A patent/AU1143599A/en not_active Abandoned
- 1998-09-29 JP JP2000516491A patent/JP2001520492A/en not_active Withdrawn
- 1998-09-29 EP EP98954234A patent/EP1023784A2/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| WO1999020061A2 (en) | 1999-04-22 |
| JP2001520492A (en) | 2001-10-30 |
| WO1999020061A3 (en) | 1999-06-24 |
| EP1023784A2 (en) | 2000-08-02 |
| AU1143599A (en) | 1999-05-03 |
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