EP1038359A2 - Estimation of transmission channels in communication systems for wireless telecommunication - Google Patents

Abstract

Various channel pulse response correlations are used in a variety of ways to improve and simplify estimation of wireless transmission channels in telecommunication systems e.g. one of two messages which are intended for another sender/receiver are used for channel estimation. In addition or alternately, the difference between two channel pulse responses is determined. If this difference falls below a given limit an average channel pulse response is formed and /or sequences of training information or test signals are not transmitted in alternate bursts. In addition or alternately, the correlation of two channel pulse responses by means of look up tables can be used to estimate subscriber speed.

Description

description

Transmission channel estimation in telecommunication systems with wireless telecommunication

In message systems with a message transmission link between a message source and a message sink, transmitting and receiving devices (transmitters and receivers) are used for message processing and transmission in which

1) the message processing and message transmission can take place in a preferred transmission direction (simplex mode) or in both transmission directions (duplex mode), 2) the message processing is analog or digital,

3) the message transmission over the long-distance transmission line is wired or on the basis of various message transmission methods FDMA (Frequency Division Multiple Access), TDMA (Time Division Multiple Access) and / or CDMA (Code Division Multiple Access) - e.g. according to radio standards such as DECT, GSM, WACS or PACS, IS-54, IS-95, PHS, PDC etc. [cf. IEEE Communications Magazine, January 1995, pages 50 to 57; D.D. Falconer et al: "Time Division Multiple Access Methods for Wireless Personal Communications] takes place wirelessly (e.g. by radio transmission).

"Message" is a superordinate term that stands for both the meaning (information) and the physical representation (signal). Despite the same Sinngehal- a message having - that same information - un ^¬ different signal forms may occur. So z. B. a ei ^¬ NEN subject message

(1) in the form of an image,

(2) as a spoken word, (3) as a written word,

(4) as an encrypted word or image be transmitted. The type of transmission according to (1) ... (3) is usually characterized by continuous (analog) signals, while the type of transmission according to (4) usually produces discontinuous signals (eg impulses, digital signals).

Based on this general definition of a messaging system, the invention relates to a method for estimating transmission channels in telecommunication systems with wireless telecommunication according to the preambles of claims 1, 6, 9 and 11 and to transceivers for estimating transmission channels in telecommunication systems with wireless Telecommunications according to the preambles of claims 22, 27, 30 and 32.

Telecommunications systems with wireless telecommunications, as described in the documents (1): Kommunikationstechnik Electronics, Berlin 45, 1995, Issue 1, Pages 10 to 14 and Issue 2, Pages 24 to 27; P. Jung, B. Steiner: "Concept of a CDMA mobile radio system with common detection for the third generation of mobile radio"; (2): Kommunikationstechnik Electronics, Berlin 41, 1991, Issue 6, pages 223 to 227 and page 234; PW Baier, P.Jung, A. Klein: "CDMA - an inexpensive multiple access method for frequency-selective and time-variant mobile radio channels"; (3): IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E79-A, No. 12, December 1996, pages 1930 to 1937; PW Baier, P. Jung: "CDMA Myths and Realities Revisited"; (4): IEEE Personal Communications, February 1995, pages 38 to 47; A. Urie, M. Streeton, C.Mourot: "An Advanced TDMA Mobile Access System for UMTS "; (5): telekom praxis, 5/1995, pages 9 to 14; PW Baier: "Spread Spectrum Technology and CDMA - an originally military technology conquered the civilian sector"; (6): IEEE Personal Communications, February 1995, pages 48 to 53; PGAndermo, LM Ewerbring: "An CDMA-Based Radio Access Design for UMTS "; (7): ITG Fachberichte 124 (1993), Berlin, Offenbach: VDE Verlag ISBN 3-8007-1965-7, pages 67 to 75; Dr. T. Zimmermann, Siemens AG: "Application of CDMA in mobile communication"; (8): telcom report 16, (1993), number 1, pages 38 to 41; Dr. T. Ketseoglou, Siemens AG and Dr. T. Zimmermann, Siemens AG: "Efficient subscriber access for the 3rd generation of mobile communication - multiple access procedures CDMA makes air interface more flexible" are shown and described with a view to a universal mobile telecommunication system (UMTS) as the future radio telecommunication scenario of the third generation designated.

The radio telecommunications scenario of the second generation is currently in the micro or macro cell range from the GSM-specific radio telecommunications system based on the FDMA / TDMA / FDD transmission principle (Frequency Division Duplex)

[Groupe Speciale Mobile or Global System for Mobile Communication; see. (1): Informatik Spektrum 14 (1991) June, No. 3, Berlin, DE; A.Mann: "The GSM standard - basis for digital European mobile radio networks", pages 137 to 152; (2): R.Steele: Mobile Radio Communications, Pentech Press, 1992

(Reprint 1994), Chapter 8: The Pan-European Digital Cellular Mobile Radio System - known as GSM, pages 677 ff .; (3): te- lekom practice 4/1993, P. S olka: "GSM radio interface - Ele ^¬ elements and functions", pages 17 and 24] and Pikozellenbe- ranging from on the FDMA / TDMA / TDD transmission principle ( Time Division Duplex) based DECT telecommunication system [Digital Enhanced (formerly: European) Cordless Telecommunication; see (1): Kommunikationstechnik Electronics 42 (1992) Jan./Feb. No. 1, Berlin, DE; U. Pilger " Structure of the DECT standard ", pages 23 to 29 in connection with the ETSI

Publication ETS 300175-1 ... October 9, 1992; (2): telcom report 16 (1993), No. 1, JH Koch: "Digital convenience for cordless telecommunications - DECT standard opens up new areas of use", pages 26 and 27; (3): tec 2/93 - The tech African magazine Ascom "Towards the universal mobile Tele ^¬ communication", pages 35 to 42; (4): Philips Telecommunication Review Vol. 49, No. 3, Sept. 1991, RJ Mulder: "DECT, a universal cordless access system "; (5): WO 93/21719 (FIG. 1 to 3 with associated description)].

FIGURE 1 shows that for the transmission of user data on the traffic channel (Traffic CHannel TCH) from the publications “(1): Informatik Spektrum 14 (1991) June, No. 3, Berlin, DE; A. Mann: "The GSM standard - the basis for digital European mobile radio networks", pages 137 to 152; (2): R. Steele: Mobile Radio Communications, Pentech Press, 1992 (Reprint 1994), Chapter 8: The Pan-European Digi tal Cell ular Mobile Radio System - known as GSM, page 677 ff.; (3): teleko praxis 4/1993, P. Smolka: "GSM radio interface - elements and functions", pages 17 and 24 "well-known TCH multi-frame, TDMA frame and TDMA time slot structure of GSM mobile radio - Concept in which the data embedded in the structure shown in accordance with the FDD principle in the uplink or uplink direction (uplink; transmission "mobile station -" base station ") in the frequency band between 890 MHz and 915 MHz and in the downlink or downlink direction ( downlink; transmission "base station -» mobile station ") in the frequency band between 935 MHz and 960 MHz.

FIGURE 2 shows that from the publication "Message Technology Electronics 42 (1992) Jan./Feb. No. 1, Berlin, DE; U. Pilger "Structure of the DECT standard", pages 23 to 29 "known

Multirah en, TDMA frame and TDMA time slot structure of the DECT mobile radio concept, in which the data embedded in the structure shown according to the TDD principle in the downlink or downlink direction (downlink; transmission “base station - ■ mobile station”) in time slots 0 ... 11 and in the uplink or uplink (uplink; transmission "mobile station -> base station") in time slots 12 ... 23.

FIGURE 3 shows, starting from the publication Nachrichtenentech ^¬ nik Elektronik, Berlin 45, 1995, Book 1, Pages 10 to 14 and Book 2, Pages 24 to 27; P. Jung, B. Steiner: “Concept of a CDMA mobile radio system with common detection for the third generation of mobile telephony "a possible FDMA / TDMA / CDMA multiple access for the uplink (uplink; transmission direction" mobile station -> base station ") and downlink (uplink; transmission direction" mobile station -> base station ") a telecommunications system with CDMA, FDMA and TDMA multiple access components, for example a joint detection CDMA mobile radio concept, in which - as with the GSM system (see FIG. 1) - the data in accordance with the FDD principle in the uplink or upward direction (uplink; transmission "mobile station -> base station") and in the downlink or downward direction (downlink; transmission "base station -» mobile station ") are transmitted in different frequency bands.

The number of participants active simultaneously in a time slot is e.g. K = 8.

FIGURE 4 shows, starting from the representation of the multiple access in FIGURE 3, that from the publication Nachrichtenentechnik Elektronik, Berlin 45, 1995, number 1, pages 10 to 14 and number 2, pages 24 to 27; P. Jung, B. Steiner: "Concept of a CDMA mobile radio system with common detection for the third generation of mobile radio", known time slot structure (burst structure) of the uplink (shown in FIG. 5 of the publication) (up link; transmission direction "handset -> base station") of the Joint Detection CDMA mobile radio concept.

The 24 data symbols of the user data blocks shown in FIG. 4 are spread using a subscriber-specific spreading code with a spreading factor of Q = 14, so that each data symbol 14 contains data elements designed as “chips”.

FIGURE 5 shows on the basis of a GSM radio scenario with, for example, two radio cells and base stations (base transceiver station) arranged therein, a first base station BTS1 (Transmitter / receiver) a first radio cell FZ1 and a second base station BTS2 (transmitter / receiver) "illuminates" a second radio cell FZ2 omnidirectionally, a FDMA / TDMA / CDMA radio scenario in which the base stations BTS1, BTS2 use a for the FDMA / TDMA / CDMA radio scenario designed air interface with several mobile stations MS1 ... MS5 (transmitter / receiver) located in the radio cells FZ1, FZ2 by wireless unidirectional or bidirectional - upward direction UL (up link) and / or downward direction DL (down link) - The base stations BTS1, BTS2 are connected in a known manner (cf. GSM telecommunication system) to a base station controller BSC (BaseStation Controller), which is used to control the base stations The base station controller BSC is on its part via a mobile switching center MSC (M obile switching center) with the higher-level telecommunications network, for example the PSTN (Public Switched Telecommunication Network). The mobile switching center MSC is the administration center for the telecommunications system shown. It takes over the complete call management and, with attached registers (not shown), the authentication of the telecommunication participants and the location monitoring in the network.

FIGURE 6 shows the basic structure of the base station BTS1, BTS2 designed as a transmitter / receiver, while FIGURE 7 shows the basic structure of the mobile station MT1 ... MT5 also designed as a transmitter / receiver. The base station BTS1, BTS2 takes over the sending and receiving of radio messages from and to the mobile station MTS1..MTS5, while the mobile station MT1 ... MT5 takes over the sending and receiving of radio messages from and to the base station BTS1, BTS2. For this purpose, the base station has a transmission antenna SAN and a reception antenna EAN, while the mobile station MT1... MT5 has an antenna ANT that can be controlled for transmission and reception by an antenna switchover AU. In the up the base station BTS1, BTS2 receives at least one radio message FN with an FDMA / TDMA / CDMA component from at least one of the mobile stations MT1 ... MT5, while the mobile station MT1 ... MT5 in the downward direction (reception path) (Receive path) receives, for example, at least one radio message FN with an FDMA / TDMA / CDMA component from at least one base station BTS1, BTS2 via the common antenna ANT. The radio message FN consists of a broadband spread carrier signal with information modulated onto data symbols.

The received carrier signal is filtered in a radio receiving device FEE and mixed down to an intermediate frequency, which in turn is subsequently sampled and quantized. After an analog / digital conversion, the signal, which has been distorted on the radio path by multipath propagation, is fed to an equalizer EQL, which largely compensates for the distortions (Stw.: Synchronization).

Subsequently, a channel estimator KS tries to estimate the transmission properties of the transmission channel TRC on which the radio message FN has been transmitted. The transmission properties of the channel are specified in the time range by the channel impulse response. In order that the channel impulse response can be estimated, the radio message FN is assigned (or in the present case by the mobile station MT1 ... MT5 or the base station BTS1, BTS2) a special additional information designed as a training information sequence in the form of a so-called Mitambel assigned.

In a subsequent data detector DD common to all received signals, the individual mobile station-specific contained in the common signal

Equalized and separated signal components in a known manner. After equalization and separation, a symbol-to- Data converter SDW converted the existing data symbols into binary data. The original bit stream is then obtained from the intermediate frequency in a demodulator DMOD before the individual time slots are assigned to the correct logical channels and thus also to the different mobile stations in a demultiplexer DMUX.

The bit sequence obtained is decoded channel by channel in a channel codec KC. Depending on the channel, the bit information becomes the control and signaling time slot or one

Voice time slot assigned and - in the case of the base station (FIGURE 6) - the control and signaling data and the voice data for transmission to the base station controller BSC jointly transferred to an interface SS responsible for signaling and voice coding / decoding (voice codec), while - in Case of the mobile station (FIGURE 7) - the control and signaling data of a control and signaling unit STSE responsible for complete signaling and control of the mobile station and the voice data are transferred to a voice codec SPC designed for voice input and output.

In the speech codec of the interface SS in the base station BTS1, BTS2, the speech data are stored in a predetermined data stream (e.g. 64kbit / s stream in the network direction or 13kbit / s stream from the network direction).

The complete control of the base station BTS1, BTS2 is carried out in a control unit STE.

In the downward direction (transmission path), the base station BTS1, BTS2 sends, for example, at least one radio message FN with an FDMA / TDMA / CDMA component to at least one of the mobile stations MT1 ... MT5, while the mobile station MT1 ... MT5 in the upward direction

(Transmission path) via the common antenna ANT, for example at least one radio message FN with an FDMA / TDMA / CDMA Component sends at least one base station BTS1, BTS2.

The transmission path begins at the base station BTS1, BTS2 in FIGURE 6 by the fact that in the channel codec KC control and signaling data and voice data received from the base station controller BSC via the interface SS are assigned to a control and signaling time slot or a voice time slot and channel by channel a bit sequence can be encoded.

The transmission path begins at the mobile station MT1 ... MT5 in FIGURE 7 with the fact that in the channel codec KC speech data received from the speech codec SPC and control and signaling data received from the control and signaling unit STSE a control and Signaling time slot or a speech time slot are assigned and these are encoded channel by channel into a bit sequence.

The bit sequence obtained in the base station BTS1, BTS2 and in the mobile station MT1 ... MT5 is in each case converted into data symbols in a data-to-symbol converter DSW. Subsequently, the data symbols are spread in a spreading device SPE with a subscriber-specific code. In the burst generator BG, consisting of a burst composer BZS and a multiplexer MUX, a training information sequence in the form of a shared message for channel estimation is then added to the spread data symbols in the burst composer BZS, and the burst information obtained in this way is set to the correct time slot in the multiplexer MUX . Finally, the burst obtained is modulated at high frequency in a modulator MOD and converted to digital / analog before the signal obtained in this way is emitted as a radio message FN via a radio transmitter FSE on the transmit antenna SAN or the common antenna ANT. In telecommunication systems with wireless telecommunication, such as the mobile radio system shown in FIG. 5, one has the known problem (cf. publications (1): Kommunikationstechnik Electronics, Berlin 45, 1995, number 1, pages 10 to 14 and number 2, pages 24 to 27; P. Jung, B. Steiner:

"Concept of a CDMA mobile radio system with common detection for the third generation of mobile radio"; (2): Kommunikationstechnik Electronics, Berlin 41, 1991, Issue 6, pages 223 to 227 and page 234; PW Baier, P. Jung, A. Klein : "CDMA - an inexpensive multiple access method for frequency-selective and time-variant mobile radio channels"; (3): IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E79-A, No. 12, Dece about 1996, pages 1930 to 1937; PW Baier, P. Jung: "CDMA Myths and Realities Revised"; (4): IEEE Personal Communications, February 1995, pages 38 to 47; A. Urie, M. Streeton, C. Mourot: "An Advanced TDMA Mobile Access System for UMTS "; (5): telekom praxis, 5/1995, pages 9 to 14; PW Baier: "Spread Spectrum Technology and CDMA - an originally military technology conquered the civilian sector"; (6): IEEE Personal Communications, February 1995, pages 48 to 53; PGAndermo, LM Ewerbring: "An CDMA-Based Radio Access Design for UMTS "; (7): ITG Fachberichte 124 (1993), Berlin, Offenbach: VDE Verlag ISBN 3-8007-1965-7, pages 67 to 75; Dr. T.Zimmermann, Siemens AG: "Application of CDMA in mobile communication"; (8): telcom report 16, (1993), number 1, pages 38 to 41; Dr. T. Ketseoglou, Siemens AG and Dr. T. Zimmermann Siemens AG: "Efficient subscriber access to the third generation of mobile communications - Much ^¬ multiple access sverfahren CDMA makes air interface more flexibly") that the transmission characteristics of the transmission path of the transmission channel and the mobile radio channel are time-variant. The transmission properties of the mobile radio channel are characterized in the time domain by the channel impulse response. Particularly in TDMA-based mobile radio systems, attempts are therefore made in a known manner to estimate the channel impulse response of the mobile radio channel. You add training sequences or test signals, so-called midambles the message to be sent - in the case of TDMA-based telecommunications systems, the burst. The channel impulse response of the mobile radio channel can then be determined with the aid of the received signal, which originates from the training sequence or the test signals.

The object on which the invention is based is to improve, simplify and optimize the estimation of wireless transmission channels in telecommunication systems.

This object is achieved on the basis of the method defined in the preamble of patent claims 1, 6, 9 and 11 by the features specified in the characterizing part of patent claims 1, 6, 9 and 11.

In addition, the problem is solved on the basis of the transmitter / receiver defined in the preamble of claims 22, 27, 30 and 32 by the features specified in the characterizing part of claims 22, 27, 30 and 32.

The idea on which the invention is based essentially consists in using correlations of different channel impulse responses. This can be achieved in that (i) a telecommunications subscriber [eg, according to FIG. 5, a system-internal subscriber at the mobile station MS1 ... MS5 and / or another system-internal subscriber at the mobile station MS1 ... MS5 ( Internal connection) or a non-system participant in the higher-level PST network (external connection)] who receives messages intended for him (in the case of TDMA-based telecommunication systems a participant to whom, for example, the time slot #n of a TDMA frame is assigned) also messages that are for other subscribers are determined and are transmitted in the same transmission direction (in the case of TDMA-based telecommunication systems, another subscriber to whom, for example, the time slot #nl of a TDMA frame is assigned) for channel estimation used. This allows a significant improvement in the bit error rate (link level performance), which is a function of bit energy to noise power density [BER = f (Eb / No)].

(ii) additionally according to claims 2 and 3 or 23 and 24 or alternatively according to claims 6 or 27 two sufficiently similar channel impulse responses which, for example according to claims 18, 19 and 20 or 38, 39 and 40 in different (not necessarily consecutive) time slots are estimated and their deviation falls below a predetermined limit, are averaged. It can thereby be achieved that a lower E _b / N _{0 is} required for a required bit error rate BER than without utilizing this information.

(iii) additionally according to claims 4 or 25 or alternatively according to claims 9 or 30 for two sufficiently similar channel impulse responses, the deviation of which falls below a predetermined limit value, for every nth transmission time slot, e.g. 41, every second burst, no training information sequence or test signals (middle tamper) is transmitted. In particular, the data rate of the respective subscriber can thereby be increased.

(iv) additionally according to claims 5 and 26 or alternatively according to claims 11 and 32, “LOOK-UP” tables for different carrier frequencies of the telecommunication system, in which the relationship “correlation coefficient <-” speed of the subscriber is related to the carrier frequency (absolute speed) "is shown. The channel estimation can be simplified with these tables. A prerequisite for creating the tables, however, is that the correlation properties of estimated channel impulse responses are examined beforehand and, depending on this, the relative speed of a subscriber is estimated. Are the estimated channel impulse responses correct? the participant moves at a slow relative speed. If the estimated channel impulse responses are not correlated, the participant moves at a high relative speed.

Further advantageous developments of the invention are specified in the remaining claims.

Exemplary embodiments of the invention are explained with reference to FIGS. 8 and 14. Show it:

FIGURE 8, starting from FIGURE 6, the basic structure of a base station according to a first embodiment

FIGURE 9, starting from FIGURE 7, the basic structure of a mobile station according to a first embodiment

FIGURE 10, starting from FIGURE 6, the basic structure of a base station according to a second embodiment

FIGURE 11, starting from FIGURE 7, shows the basic structure of a mobile station according to a second exemplary embodiment

FIGURE 12, starting from FIGURE 6, the basic structure of a base station according to a third embodiment

FIGURE 13, starting from FIGURE 7, shows the basic structure of a mobile station according to a third exemplary embodiment

FIGURE 14, starting from FIGURE 6, the basic structure of a base station according to a fourth embodiment.

FIGURES 8 and 9 show the basic structure of the base station BTS1, BTS2 (FIGURE 8) and the mobile station, respectively, based on FIGURES 6 and 7

MT1 ... MT5 (FIGURE 9). The main difference between the respective structure according to FIGURES 6 and 7 and the respective Structure according to FIGURES 8 and 9 consists in that a modified channel estimator KS 'is used in the respective structure according to FIGURES 8 and 9. This channel estimator KS 'is designed such that, for example, starting from FIGURE 5, a system-internal participant at the mobile station MS1 ... MS5 and / or another system-internal participant at the mobile station MS1 ... MS5 (internal connection) or a system-external participant in higher-level PST network (external connection) that receives messages intended for it (in the case of TDMA-based telecommunication systems, a subscriber to whom, for example, the time slot "n" of a TDMA frame is assigned) also messages that are intended for other subscribers and in the same transmission direction are transmitted (in the case of TDMA-based telecommunications systems, another subscriber to whom, for example, the time slot “n-1” of a TDMA frame is assigned) are used for channel estimation. As a result, a significant improvement in the bit error rate or link level performance can be achieved, which is a function of bit energy and noise power density [BER = f (E / N ₀ )] _. is.

FIGURES 10 and 11 show, according to a second exemplary embodiment, starting from FIGURES 6 and 7, the basic structure of the base station BTS1, BTS2 (FIGURE 10) and the mobile station MT1 ... MT5 (FIGURE 11). The essential difference between the respective structure according to FIGURES 6 and 7 and the respective structure according to FIGURES 10 and 11 is that an evaluation device AWE is provided in the respective structure according to FIGURES 10 and 11. This evaluation device AWE is bidirectionally assigned to or connected to the channel estimator KS and the control unit STE or the control and signaling unit STSE and forms special channel estimation means with these. These channel estimation means differ from the respective channel estimator in that, by means of the evaluation device AWE controlled by the control unit STE or the control and signaling unit STSE, two of the respective channel estimators KS co κ> κ_ μ>μ> π o (-π o Cπ o Cπ

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Claims

claims 1. Method for estimating transmission channels in telecommunication systems with wireless telecommunication, whereby between transmitter (MS1 ... MS5, BTSl, BTS2) and receiver (BTSl, BTS2, MS1 ... MS5) of the telecommunication systems messages via the transmission channels (TRC) uni - or transmitted bidirectionally, characterized in that a first receiver (BTS1, BTS2, MS1 ... MS5) which receives a first message sent by a first transmitter (MS1 ... MS5, BTS1, BTS2), at least one further Message sent by the first transmitter (MS1 ... MS5, BTS1, BTS2) and / or another transmitter (MS1 ... MS5, BTS1, BTS2) in the same transmission direction to at least one other receiver (BTS1, BTS2, MS1 ... MS5) is used for the channel estimation. 2. The method according to claim 1, characterized in that the telecommunication system is a telecommunication system based on the TDMA multiple access method. 3. The method according to claim 2, characterized in that e (a) the messages are assigned to time slots, (b) channel impulse responses contained in the messages are estimated for the time slots, (c) for a first reception time slot of a first transmitter DERS / receiver (BTSl, BTS2, MS1 ... MS5) a first Kanalim ^¬ impulse response is estimated, (d) for a second receive time slot, a second channel impulse response is estimated from the first transmitter / receiver (MS1 ... MS5 BTSl, BTS2), (e) provides a sufficient similarity between the first channel impulse response and the second channel impulse response Festge ^¬ when a Difference by which the first channel im- pulse response deviates from the second channel impulse response, falls below a predetermined limit value, (f) an average channel impulse response is formed from the first channel impulse response and the second channel impulse response if these are sufficiently similar. 4. The method according to claim 2 or 3, characterized in that (a) the messages are assigned to time slots, (b) channel impulse responses contained in the messages are estimated for the time slots, (c) a first channel impulse response is estimated for a first reception time slot of a first transmitter / receiver (BTSl, BTS2, MS1 ... MS5), (d) for a second reception time slot of the first transmitter / receiver (BTSl, BTS2, MS1 ... MS5) a second channel impulse response is estimated, , a predetermined threshold value when a difference by which the first Kanalim ^¬ impulse response deviates from the second channel impulse response (e) a sufficient similarity between the first channel impulse response and the second channel impulse response is fixed, below, (f) for every n-th transmission time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) with n greater than 1, there is no message in the respective transmitted channel estimation message Training information sequence is transmitted, if the first channel impulse response and the second channel impulse response rea ^¬ are accordingly similar. 5. The method according to any one of claims 1 to 4, characterized in that (a) a first channel impulse response contained in the data transmitted in frequency bands messages of a stationary Sen ^¬ is estimated DERS / receiver (BTSl, BTS2, MS1 ... MS5), (b) a second Kanalimpulsant contained in the message ^¬ word of the stationary transmitter / receiver (BTSl, BTS2) ge ^¬ estimates is (c) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed in relation to the respective frequency band of a mobile transmitter / receiver (MS1 ... MS5) is defined as slow if the first channel impulse response and the second channel impulse response are sufficiently similar, (e) the relationship “correlation coefficient -» speed "Specifying" LOOK UP "table is created, (f) a predetermined number of subsequent channel impulse responses of the stationary transmitter / receiver (BTS1, BTS2) are estimated on the basis of the" LOOK UP "table. 6. Method for estimating transmission channels of telecommunication systems with wireless telecommunication, wherein (a) messages assigned to time slots are transmitted bidirectionally between the transmitter (MT1 ... MT5, BTS1, BTS2) and receiver (BTSl, BTS2, MS1 ... MS5) of the telecommunication systems, via the transmission channels (TRC), are estimated (b) for the time slots in the message Ka ^¬ given nalimpulsantworten, characterized in that (c) for a first receiving time slot a first Kanalim ^¬ is impulse response estimate of a first transmitter / receiver (MS1 ... MS5 BTSl, BTS2) , (d) a second channel impulse response is estimated for a second reception time slot of the first transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (e) a sufficient similarity between the first channel impulse response and the second channel impulse response Festge ^¬ represents, when a difference by which the first Kanalim ^¬ impulse response deviates from the second channel impulse response, NEN predetermined limit egg below, o co N>) μ> μ » Cπ o Cπ o Cπ o Cπ Öd tu cn μ- CΛ a Φ μ > o ¹ o ^ CJ _* 1 m P ⁾ he Φ Φ L Φ ω Ω tr P>: rt N rt Z Φ μ a φ d • 9. A method for estimating transmission channels in telecommunication systems with wireless telecommunication, wherein (a) Messages between the transmitter (MT1 ... MT5, BTS1, BTS2) and receiver (BTSl, BTS2, MS1 ... MS5) of the telecommunication systems are assigned time slots via the transmission channels. (TRC) are transmitted bidirectionally, (b) channel impulse responses contained in the messages are estimated, characterized in that (c) a first channel impulse response is estimated for a first reception time slot of a first transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (d) a second channel impulse response is estimated for a second reception time slot of the first transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (e) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (f) th n-for each transmission time slot of the transmitter / receiver (BTSl, BTS2, MS1 ... MS5) with n greater than 1 not being transmitted in each ^¬ weils transmitted message for channel estimation training information sequence given as if the first channel impulse response and the second channel impulse response rea ^¬ accordingly similar. 10. The method according to claim 9, characterized in ^¬ net that (a) a first channel impulse response contained in the transmitted messages in frequency bands of a stationary Sen ^¬ DERS / receiver (BTSl, BTS2) is estimated (b) contained in the second message Kanalimpulsant ^¬ word of the stationary transmitter / receiver (BTSl, BTS2) overall estimates is (c) established a sufficient similarity between the first channel impulse response and the second channel impulse response is set if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed in relation to the respective frequency band of a mobile transmitter / receiver (MS1 ... MS5) is defined as slow if the first channel impulse response and the second channel impulse response are sufficiently similar (e) a "LOOK UP" table indicating the relationship "correlation coefficient <-» speed "is created, (f) a predetermined number of subsequent channel impulse responses of the stationary transmitter / receiver (BTS1, BTS2) on the basis of the" LOOK UP "- Table to be estimated. 11. Method for estimating transmission channels in telecommunication systems with wireless telecommunication, whereby between transmitter (MT1 ... MT5, BTSl, BTS2) and receiver (BTSl, BTS2, MS1 ... MS5) of the telecommunication systems messages about the transmission channels (TRC ) are transmitted bidirectionally in frequency bands, characterized in that (a) a first channel impulse response of a stationary transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (d) a second channel impulse response of the stationary transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (c) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed in relation to the respective frequency band of a mobile transmitter / receiver (MS1 ... MS5) is defined as slow if the first channel impulse response and the second channel impulse response are sufficiently similar, (e) a “LOOK UP” table indicating the relationship “correlation coefficient speed” is created, (f) a predetermined number of subsequent channel impulse responses of the stationary transmitter / receiver (BTS1, BTS2) are estimated on the basis of the “LOOK UP” table. 12. The method according to any one of claims 1 to 11, characterized in that the telecommunications system is a telecommunications system based on the TDMA / CDMA multiple access methods. 13. The method according to claim 12, characterized in that the telecommunications system is a JD-CDMA telecommunications system. 14. The method according to claim 1 or 2, characterized in that the first transmitter (MS1 ... MS5, BTS1, BTS2) is a base station and the first receiver (BTSl, BTS2, MS1 ... MS5) is a mobile station . 15. The method according to any one of claims 3 to 13, characterized in that the first transmitter / receiver (BTS1, BTS2, MS1 ... MS5) is a base station. 16. The method according to any one of claims 3 to 13, characterized in that the first transmitter / receiver (BTS1, BTS2, MS1 ... MS5) is a mobile station. 17. The method according to claim 5, 8, 10 or 11, characterized in that the stationary transmitter / receiver (BTS1, BTS2) is a base station and the mobile transmitter / receiver (MS1 ... MS5) is a mobile station. 18. The method according to any one of claims 3 to 17, characterized in that the first reception time slot and the second reception time slot follow one another directly. 19. The method according to any one of claims 3 to 18, characterized in that the first receive time slot and the second receive time slot are in a TDMA frame. 20. The method according to any one of claims 3 to 18, characterized in that the first receive time slot and the second receive time slot are in different TDMA frames. 21. The method according to claim 4, 7 or 9, characterized in that the number "n" is equal to 2. 22. Transmitter / receiver for estimating transmission channels in telecommunication systems with wireless telecommunication, messages between the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) and a remote station of the telecommunication system designed as a transmitter / receiver being used, messages about the transmission channels (TRC ) are transmitted unidirectionally or bidirectionally, with channel estimation means (KS), characterized in that the channel estimation means (KS ') are designed such that when the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) one of the opposite station received first message received, at least one further message, which is transmitted from the remote station and / or further remote stations in the same transmission direction to at least one further transmitter / receiver (BTS1, BTS2, MS1 ... MS5), is used for the channel estimation . 23. Transmitter / receiver according to claim 22, characterized in that the telecommunication system is a telecommunication system based on the TDMA multiple access method. 24. Transmitter / receiver according to claim 23, characterized in that the messages are assigned time slots and that the channel estimation means (KS, STE, STSE, AWE) are designed such that (a) channel impulse responses contained in the messages are estimated for the time slots, (b) a first channel impulse response is estimated for a first reception time slot of the transmitter / receiver (BTSl, BTS2, MS1 ... MS5), (c) for a second reception time slot of the transmitter / receiver (BTSl, BTS2, MS1 ... MS5) a second channel impulse response is estimated (d) a sufficient similarity between the first channel impulse response and the second channel impulse response fixed represents, when a difference by which deviates the first channel impulse response from the second channel impulse response falls below ei ^¬ NEN predetermined limit value, (e) a mean pulse response channel impulse response from the first Kanalim ^¬ and second channel impulse response is formed, if they are sufficiently similar. 25. Transmitter / receiver according to claim 23 or 24, characterized in that the messages are assigned time slots and that the channel estimation means (KS, STE, STSE, AWE ') are designed such that (a) channel impulse responses contained in the messages are estimated for the time slots, (b) a first channel impulse response is estimated for a first reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (c) a second channel impulse response is estimated for a second reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (d) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (e) for every n-th transmission time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) with n greater than 1, no training information sequence contained in the respectively transmitted message for channel estimation is transmitted if the first channel impulse response and the second channel impulse response are sufficiently similar. 26. Transmitter / receiver according to one of claims 22 to 25, characterized in that the channel estimation means (KS, STE, SP) are designed such that (a) a first channel impulse response of the transmitter / receiver contained in the messages transmitted in frequency bands (BTSl, BTS2) is estimated (b) a second channel impulse response of the transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (c) a sufficient similarity between the first channel impulse response and the second channel impulse response Festge ^¬ represents, when a difference by which the first Kanalim ^¬ impulse response deviates from the second channel impulse response falls below ei ^¬ NEN predetermined limit value, (d) the speed based on the particular frequency band as a transmitter / receiver configured mobile remote station is defined as slow if the first Kanalim ^¬ impulse response and the second channel impulse response are sufficiently similar, (e) a “LOOK-UP” table indicating the correlation “correlation coefficient <-“ speed ”is created, (f) a predetermined number of subsequent channel impulse responses of the transmitter / receiver (BTS1, BTS2) are estimated on the basis of the “LOOK-UP” table. 27. Transmitter / receiver for estimating transmission channels in telecommunication systems with wireless telecommunication, messages between the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) and a counter station of the telecommunication systems designed as a transceiver being used to assign time slots to messages about the transmission channels (TRC) are transmitted bidirectionally, with channel estimation means (KS), which estimate channel impulse responses contained in the messages for the time slots, characterized in that the channel estimation means (KS, STE, STSE, AWE) are designed such that (a) a first channel impulse response is estimated for a first reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (b) a second channel impulse response is estimated for a second reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (c) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined when a difference by which deviates the first channel impulse response from the second channel impulse response falls below ei ^¬ NEN predetermined limit value, (d) an average channel impulse response from the first Kanalim ^¬ impulse response and the second channel impulse response is formed, if they are sufficiently similar. 28, transmitter / receiver according to claim 27, labeled in characterized ^¬ characterized in that the channel estimation means (KS, STE, STSE, AR ') are formed such that th n for each transmission time slot of the transmitter / receiver (BTSl, BTS2, MS1 .. .MS5) with n greater than 1, no training information sequence contained in the respectively transmitted message for channel estimation is transmitted when the first Channel impulse response and the second channel impulse response are sufficiently similar. 29. Transmitter / receiver according to claim 27 or 28, characterized in that the channel estimation means (KS, STE, SP) are designed such that (a) a first channel impulse response of the transmitter / receiver contained in the messages transmitted in frequency bands (BTSl, BTS2) is estimated, (b) a second channel impulse response of the transmitter / receiver (BTSl, BTS2) contained in the messages is estimated, (c) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed based on the particular frequency band of a formed as a transmitter / receiver mobile counter ^¬ station is defined as slow if the first channel impulse response and the second channel impulse response are sufficiently similar, (e) the relationship "correlation coefficient - Ge ^¬ speed" indicating "LOOK-UP" is created table, (f) a predetermined number of subsequent channel impulse responses of the transmitter / receiver (BTS1, BTS2) based on the "LOOK-UP" table can be estimated. 30. Transmitter / receiver for estimating transmission channels in telecommunication systems with wireless telecommunication, with time slots allocated to messages via the transmission channels (TRC.) Between the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) and a remote station of the telecommunication systems designed as a transmitter / receiver ) are transmitted bidirectionally, with channel estimation means (KS), which estimate channel impulse responses contained in the messages for the time slots, characterized in that the channel estimation means (10) are designed such that (a) a first channel pulse response is estimated for a first reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (b) a second channel impulse response is estimated for a second reception time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5), (c) a sufficient similarity between the first channel impulse response and the second channel impulse response is determined if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) for every n-th transmission time slot of the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) with n greater than 1, no training information sequence contained in the respectively transmitted message for channel estimation is transmitted if the first channel impulse response and the second channel impulse response are sufficiently similar. 31, transmitter / receiver according to claim 30, characterized labeled in ^¬ characterized in that the channel estimation means (KS, STE, SP) are designed such that (a) a first channel impulse response of the transmitter / receiver contained in the messages transmitted in frequency bands (BTSl, BTS2) is estimated (b) a second channel impulse response of the transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (c) a sufficient similarity between the first channel impulse response and the second channel impulse response Festge ^¬ represents when a difference by which the first Kanalim ^¬ impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed based on the particular frequency band formed as a transmitter / receiver mobile station counter ^¬ as defined slowly when the first Kanalim- pulse response and the second channel impulse response are sufficiently similar, (e) a "LOOK-UP" table indicating the relationship "correlation coefficient <-> speed" is created, (f) a predetermined number of subsequent channel impulse responses of the transmitter / receiver (BTS1, BTS2) based on the "LOOK-UP" -Table are estimated. 32. Transmitter / receiver for estimating transmission channels in telecommunication systems with wireless telecommunications, with messages about the transmission channels (TRC) in between the transmitter / receiver (BTS1, BTS2, MS1 ... MS5) and a remote station of the telecommunication system designed as a transmitter / receiver Frequency bands are transmitted bidirectionally, with channel estimation means (KS) which estimate channel impulse responses contained in the messages, characterized in that the channel estimation means (KS, STE, SP) are designed such that (a) a first channel impulse response of the transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (b) a second channel impulse response of the transmitter / receiver (BTS1, BTS2) contained in the messages is estimated, (c) a sufficient similarity is found between the first channel impulse response and the second channel impulse response if a difference by which the first channel impulse response deviates from the second channel impulse response falls below a predetermined limit value, (d) the speed is defined as slow in relation to the respective frequency band of a mobile counter station designed as a transmitter / receiver if the first channel impulse response and the second channel impulse response are sufficiently similar, (e) a "LOOK-UP" table indicating the relationship "correlation coefficient - speed" is created, (f) a predetermined number of subsequent channel impulse responses of the transmitter / receiver (BTS1, BTS2) on the basis of the "LOOK-UP" table to be appreciated. 33. Transmitter / receiver according to one of claims 22 to 31, characterized in that the telecommunication system is a telecommunication system based on the TDMA / CDMA multiple access methods. 34. Transmitter / receiver according to claim 33, characterized in that the telecommunication system is a JD-CDMA telecommunication system. 35. Transmitter / receiver according to one of claims 22 to 34, characterized by a base station or mobile station. 36. Transmitter / receiver according to one of claims 22 to 35, characterized in that the remote station designed as a transmitter / receiver is a mobile station or base station. 37. Transmitter / receiver according to claim 26, 29, 31 or 32, characterized in that the transmitter / receiver (BTS1, BTS2) is a base station and the mobile remote station designed as a transmitter / receiver is a mobile station. 38. Transmitter / receiver according to one of claims 24 to 37, characterized in that the first reception time slot and the second reception time slot follow one another directly. 39. Transmitter / receiver according to one of claims 24 to 38, characterized in that the first receive time slot and the second receive time slot are in a TDMA frame. 40. Transmitter / receiver according to one of claims 24 to 38, characterized in that the first receive time slot and the second receive time slot are in different TDMA frames. 41. Transmitter / receiver according to claim 25, 28 or 30, characterized in that the number "n" is 2.