DE10311337B3 - Coded pilot signal processing method in mobile radio receiver for mobile telecommunications provides frequency error estimation via frequency error symbol pairs obtained by decoding adjacent symbols - Google Patents

Abstract

The processing method uses separation of at least 2 transmitted coded signals for time offset pilot channel paths at the reception side, with frequency error estimation for the received signals by determination of a frequency error symbol pair by decoding 2 adjacent symbols within a frame. Adjacent symbol pairs are multiplied for providing phasors summated to provide an intermediate result, with elimination of interference terms by summating an even number of phasors for each reception path. An independent claim for a mobile radio receiver is also included.

Description

The The invention relates to a method for preprocessing coded pilot channel signals in a mobile radio receiver. The invention further relates to a mobile radio receiver execution of such a process.

The Telecommunications, especially mobile communications, belongs today the fastest developing technologies. In the area of mobile radio is currently undergoing standardization and development the so-called third generation of mobile communications, which works with the term UMTS (Universal Mobile Telecommunications System) and which is a global uniform mobile radio standard provides.

The UMTS standard looks for the transfer from the base station to the handset an operating mode before which the signal over at the same time at least two antennas is transmitted. This results in the receiver of the handset generally facing one only one used transmission antenna significantly improved reception quality.

1 shows a simplified block diagram for a known transmission from a base station BTS to a handset via a pilot channel CPICH (Common Pilot Channel) with handset frequency estimation. In order to ensure that the two signals can be separated for the pilot channel CPICH, the signal to be transmitted is initially in the path of the antenna 2 modulated with a code that is orthogonal to the transmitted signal in the path of the antenna 1 causes. This so-called TxDiv coding (TxDiv = transmitter diversity) takes place cyclically on a frame basis and is formed by repeating a typically 4-symbol long pattern. As an example of TxDiv coding, the STTD coding (STTD = Switched Time Transmitter Diversity) is to be assumed below. If the frame limit is exceeded, however, there is an irregularity in the coding pattern. The reason for this is that the number of 150 symbols per frame is not an integer multiple of the symbol pattern length 4 is. The same problem occurs with slot-based processing of received symbols, since possible sequences with 8 or 12 symbols also do not coincide with the 10 symbols per slot. 2 clarifies this fact.

The signals can be separated for the constant symbol sequence of the pilot channel in such a way that two successive symbols - starting with an even symbol number and counting according to 2 - be summed once without and once with previous STTD demodulation. Since a signal component of an antenna path is typically eliminated due to the orthogonality of the STTD-modulated signals, the signal of the antenna path is approximately obtained in the first case 1 , in the latter that of the antenna path 2 ,

On Frequency error in the receiver of the handset affects the constant symbol sequence of the pilot channel such that between two consecutive symbols one Phase difference exists that is directly related to the Frequency offset stands. The size of this Phase difference can e.g. can be determined from that the current pair of symbols obtained with the conjugate complex Result of the preceding pair of symbols is multiplied. The The result is a phasor (complex pointer), in its phase the phase difference between the two values forming the phasor is included.

While in normal operating mode (no STTD modulation / demodulation) on each other following arriving pilot channel symbols used for phasor formation can be In the case of STTD-modulated signals, the STTD coding must first be decoded become. Subsequently have to go through Combining the decoded symbols into symbol pairs the signals of the two antenna paths are separated from one another. Problematic the fact is that the result of the decoding and signal separation mostly through a disturbance term is falsified that of the one to be valued Frequency error, the phase and power difference between the Signals of the two antenna paths and the coding sequence of the two Depends on symbols. The size of the disturbance is with multipath propagation for each path is different and also varies over time. The sign of the disturbance depends on from the coding sequence of the two pairs of symbols {+ –– +} or {- ++ -} and alternate with successive use of all successive symbols.

3 shows an example of the previously used symbol processing in the area of the frame boundary, in particular if an average value is formed across it. "U" denotes the desired phasor, the phase of which contains the phase difference between two adjacent pairs of symbols. "Ε" is the disturbance term that falsifies the phasor result in a complex manner. To simplify matters 3 this fault term is assumed to be constant over time. In the case of slot-based data processing, odd averaging length or averaging over the coding irregularity at the frame boundary, falsification of the result is inevitable.

In the handset, a frequency error estimate is also carried out for the received data and signals. This typically happens in the the AFC unit (AFC = Automatic Frequency Correction) arranged downstream of the so-called RAKE unit. For the greatest possible flexibility within the mobile radio system, it is recommended that the AFC unit be able to carry out a measurement both on several signal paths of a base station BTS and on signal paths of different base stations. In 4 is a corresponding transmission situation, for example, as shown in the "soft hand-over".

To the so-called delay compensation and the deinterleaving and Despreading (descramble, despread) in the RAKE unit hits the received signals a pilot channel of a base station for further processing in the AFC unit more or less synchronously. However, the problem is that different between the pilot channels Base stations almost always have a certain time offset that an arbitrary multiple of symbols within a UMTS frame can be. In this case, the AFC unit must be able to different base stations individually with different Process offset and frame start. The data of each RAKE unit fingers usually have different, Base station specific distances to the frame boundary on and need hence different STTD symbols for decoding them. Also the summary of the symbol pairs for The different antenna paths are separated in terms of time Base stations specific. About that out must for each base station has its own dedicated control logic in the AFC unit to detect the exceptional situation at the frame boundary and treat accordingly. Finally is the time for the Completion of intermediate results different for each base station.

• – Es existiert meist eine durch einen Störterm verursachte Messwertverfälschung.
• – Es existieren zeitlich beliebig gegeneinander verschobene Signalpfade bzw. Frames (insbesondere CPICH-Frames) verschiedener Basisstationen.

In summary, it can be said that the third generation mobile radio reception systems developed to date, in particular the UMTS reception systems, are inherent in the problems listed below:

• - There is usually a measurement error caused by a fault.
• - There are signal paths or frames (in particular CPICH frames) of different base stations shifted at any time.

The following approaches have been used to solve these problems:
The falsification of measured values can be reduced by combining several paths and using them averaged over a longer period to generate measured values. However, this solution has little flexibility in path selection and a more or less large variance in measured values in today's systems. In addition, an acceptable measurement result is typically tied to a sometimes very high number of different paths, which is not always guaranteed.

The The problem of temporal path shifts can be solved by a very large buffer to solve, the reading of data by the RAKE unit and processing decoupled from each other by the AFC unit. So the signal paths of all base stations largely synchronized by the respective AFC unit of a handset can be processed. This solution works however a very large one Memory for temporary storage of the received data and signals along the different paths. This comparatively very large Buffer storage is an additional cost aspect, the particularly in the highly competitive Mobile communications market where the different devices differ from each other differ in particular in their final price, mostly not on the market side is accepted. About that can out the received data or signals for further processing only with a very large one in some cases time delay be provided, which is a lower system performance and thus reducing functionality.

A alternative solution for the The problem of temporal path shifts is the AFC unit to implement completely in software which the processing the data streams of the individual signal paths that are not synchronized in time controls. A key disadvantage of this solution is that it does resulting high bus load caused by data transmission between the RAKE unit and the digital signal processor. Moreover the signal processor will be very busy and stand still at least partially other functions of the mobile radio receiver no longer to disposal.

The Problems caused by measurement falsification a disturbance term and the temporal path shifts are the receiving devices third generation of mobile communications is therefore not yet satisfactory solved.

In the abstract of the Japanese patent application JP 08 22 32 39 A describes a transmission system for pilot signals. In the European patent application EP 1 189 360 A2 is particularly in the 5 describes a conventional method for evaluating detected frame boundaries and encrypted codes. A device for demodulating pilot symbols and for error measurement is specified there, which demodulates a pilot symbol on the general pilot channel and the Measures number of errors in the pilot symbol.

outgoing The present invention resides in the problem described above therefore the task of providing an apparatus and a method, which enable an improved frequency error estimation on the handset side.

The Process-related task is inventively by a method with the Features of claim 1 solved.

Accordingly, one is Method for preprocessing coded pilot channel signals in one pager provided, in which a reception-side separation of at least two, coded signals transmitted by a transmitter of a mobile radio system, the for any time-delayed pilot channel paths in the form of frames with each of a fixed number of symbols is made at frequency error estimation of the received signals being used to determine a frequency error symbol pairs by Decoding two adjacent symbols within a frame can be formed and each adjacent pair of symbols after forming the conjugate complex value of one of the symbol pairs multiplied and the like accumulated phasors summed up to form an intermediate result and, in order to eliminate a disturbance when calculating the Intermediate result an even number of phasors per recipient path is summed up.

According to the device-related task by a mobile radio receiver with the Features of claim 19 solved.

Accordingly, one is pager with a receiving device for receiving a via a transmission channel signal sent by a base station, one downstream of the receiving device RAKE receiving unit with several delay devices connected in parallel to detect the over the different signal paths transmitted Signal components of the transmitted signal, an AFC circuit for automatic Frequency correction and combining means for assembling the signal components to an estimated Receive signal provided.

The The idea underlying the present invention is that per path for each intermediate result always an even number of symbol pairs is used. Compensation for an accumulation error that occurs is done by restriction to even-numbered accumulation lengths. For the The falsification of measured values can be the period of two successive pairs of symbols approximately can be assumed to be constant. By the alternating sign this compensates for the error. This is very simple, however, in spite of the very effective way, the problem of measurement falsification solved.

advantageous Refinements and developments are the subclaims as well the description with reference to the drawing.

In In one embodiment, the frequency error estimation received signals received by a mobile radio receiver, decoded and separated from each other.

at The signals received from a pilot channel are typically around time-coded signals, which due to their coding to each other are orthogonal. The encoded signals are generally modulated by TxDiv Receive signals. It is particularly advantageous if the coded Signals are STTD modulated.

An intermediate result A for a normal accumulation, in which no short-term accumulation takes place before the frame limit, is calculated as follows:

there M is the number of signal paths within a group or Denoted cell and with P are the symbols or symbol pairs of the Pilot channel called. The index m denotes the respective signal path and the indices i, i-D denote the sequence of the received symbol pairs. D indicates the respective integration mode, with j is the selection denotes an antenna and a indicates the symbol within of a frame was started with the calculation. e + 1 is in the case of the TxDiv mode typically 2 (short-term accumulation) or 4 and typically 4 in the case of normal mode (short-term accumulation) or 8. M typically moves between 1 and 4. The first conjugated with a factor of the product (*) is complex.

In the case, that through coding - for example with STTD coding - one irregularity at the frame boundary intermediate results are not formed across them, since this may lead to an additional measurement falsification to lead would. The frame boundary is thus detected and taken into account for every Group, cell or base station without the hardware downstream digital signal processor must intervene.

Due to the special treatment of the frame boundary due to the irregularity at the frame boundary, part of the received data cannot be used for the measurement value formation. This is particularly problematic if a large number of phasors are used to form the intermediate result. In this case, the number of data not used could be very large. However, in order to keep the number of unused input data as low as possible, depending on the time of completion of the last calculated intermediate result, another intermediate result is formed immediately before the frame boundary by accumulation over a smaller number of phasors obtained from symbol pairs (see 5 ). In this way, the received input data is used in the best possible way.

For example can with a normal accumulation of 4 phasors for an intermediate result short-term accumulation, only 2 phasors can be used.

The The value of the short-term accumulation is advantageously determined by appropriate Scaling to the order of magnitude adjusted to the normal interim results. If e.g. B. short-term accumulation only comprises half as many phasors as normal accumulation, so the result is scaled to double. Independent of The start time and offset of a group can thus be kept constant 17 intermediate results per frame in the case of a normal accumulation length of Generate 8 symbols or 4 symbol pairs.

In An advantageous embodiment is the calculation of intermediate results already started within one frame due to accumulation. It will not just the next one Waited for the beginning of a frame, which on the one hand means the number does not used data is kept low and a delay largely is avoided.

The Problem of a time shift between the signal paths is according to the invention Grouping the delay devices (RAKE fingers) the RAKE unit. The data signals of the RAKE fingers are the same base station are organized in groups, the grouped by the so RAKE fingers received signals are treated together, in particular processed, integrated and saved in a group-specific manner. Possibly existing time shifts between the so Groups formed by the delay facilities of the RAKE unit not compensated.

In One embodiment is delays of the individual recipient paths within each group using a reference time scale for specific groups balanced.

In a further embodiment are dependent on the time delay of the individual groups the calculation of the intermediate results to different Time points carried out based on the reference time scale.

In a further embodiment depends on the index of the symbol within that belonging to a group Frame history after the completion of the last complete interim result with the full number of phasors before the end of a frame Another intermediate result for accumulation over a smaller number of phasors educated.

In an embodiment can the signal parts of from different transmitters of a mobile radio system transmitted signals separated from each other before the frequency error estimation become.

In an embodiment can several groups can be assigned to the same base station.

• – Vorbereitung,
• – Datenverarbeitung,
• – Nachbereitung.

In one embodiment, a sequential control system is provided for at least one data path, the sequential control system being divided into the following three phases:

• - Preparation,
• - data processing,
• - Postprocessing.

In front- and post-processing include parameter management and group-specific control and switching processes. In the main part of data processing the data of each RAKE finger are processed in a loop. The main part thus represents the course of the actual data path with the calculation of the interim results.

In an embodiment there is the possibility of any time To be able to edit offsets of the frame course between the groups. The result necessary group-specific signaling of completed accumulations can advantageously be stored in certain RAM areas become.

In One embodiment is an activation of the special control mechanisms for example an STTD coding of the transmission mode of the depending on the group.

In one embodiment, several delay devices are used as a criterion for grouping to a group of the same base station whose membership to the signal paths of the same base station is used with a uniform frame course.

The Problem of the temporal shift of the frame course between the Groups is according to the invention a special sequence control circuit (FSM = Finite State Machine) while accumulation and resolved at the frame boundary. The sequence control circuit is typically part of the AFC unit and is implemented in the hardware part of the mobile radio receiver. This Sequence control circuit controls the typical hardware processing steps for the incoming signals of the RAKE fingers group-specific - and thus also base stations specific - in dependence of group-specific parameters. This will preprocess enabled in the hardware of the mobile radio receiver. It also will also the bus load between the hardware and the digital signal processor - or the software implemented in it - as well reduces the load on the signal processor.

In a further embodiment is the sequence control circuit as a hardware circuit, in particular as a hard-wired logic circuit.

In In one embodiment, the information regarding the above mechanisms mentioned critical parameter changes of a signal processor to the hardware of the mobile radio receiver, for example to a Program controlled unit or a control logic circuit forwarded.

In one configuration controls, processes and stores a group-specific one Sequence control circuit the hardware processing steps, in particular also depending a time offset of each group to an externally generated reference time scale from.

The Reference time scale is typically generated externally and can be used for Example with a symbol counter be implemented. For this purpose, group-specific Symbol counter Reference times and offsets generated. A counter can be used as a symbol counter which is incremented with each new pilot channel symbol and at the end of a frame (e.g. after the meter reading 149) count again at 0 starts.

In Another embodiment is a reference counter, in particular a group counter working reference counter, provided about whose counter reading the exact position can be determined within a frame.

In a further embodiment, an input buffer is provided, which is connected downstream of the receiving unit and which is buffering of the received data.

The Invention is described below with reference to the figures of the drawing specified embodiments explained in more detail. It shows:

1 a block diagram for a known transmission from a base station to a handset over a physical transmission channel;

2 the coding pattern in the area of the frame boundary in the case of a TxDiv mode;

3 the previously used symbol processing in the area of the frame boundary using an exemplary embodiment, in particular also when averaging;

4 a block diagram for a known transmission, in which a calculation of the intermediate results is carried out both on several signal paths of a base station and on signal paths of different base stations;

5 a symbol processing according to the invention in the area of the frame boundary, in which a smaller number of phasors is used to form an intermediate result by accumulation;

6 using a simple model, the data transmission from a base station to a mobile subscriber;

7 based on a block diagram the general structure of a mobile radio receiver;

8th the block diagram of a section of a mobile radio receiver according to the invention accordingly 7 having a control logic circuit according to the invention;

9 based on a table, the operation of the sequence control circuit or FSM unit according to the invention, for example 8th ,

In All figures in the drawing have the same or functionally identical elements and signals - if nothing other is specified - the same been designated.

6 shows a simple model of data transmission from a base station to a mobile subscriber. In 6 is with 1 called a mobile radio system. In the following figures from a mobile radio system 1 based on the UMTS standard, in which the data are STTD-encoded or were generally transmitted in TxDiv mode.

In the base station 2 a data stream d (t) is generated in the base station 2 spread, STTD-coded and scrambling into a transmission signal s (t) and via the UMTS transmitter 3 is sent. For this purpose, the data streams d (t) are in one 6 Spreading circuit, not shown, with ge orthogonal pairs STTD codes spread and coded. The spread and coded signal s (t) passes through the physical channel 4 as a reception signal e (t) to the UMTS receiver 5 of the mobile subscriber 6 , Descrambling, despreading and decoding of the received signal e (t) into an estimated data stream d '(t), which ideally corresponds to the data stream d (t), takes place in the receiver.

7 shows in a detailed representation the structure of a mobile radio receiver according to the invention 5 , That from the mobile subscriber 6 via a receiving antenna 10 received signal e (t) is a RAKE receiving circuit 11 fed. The receiving circuit 11 has several in 7 Signal paths (not shown) which run parallel to one another and each consist of a delay device, a descrambling circuit and a despreading circuit. The various signal paths connected in parallel are also referred to as RAKE fingers. Through the RAKE reception circuit 11 are the different signal components of the transmitted transmission signal e (t), which are due to the different signal paths of the physical transmission channel 4 arise, recorded. The delay device takes this into account 12 the different signal delay delays on the different signal paths of the transmission channel 4 , The various signal components of the received signal e (t) are descrambled and despreaded in the various RAKE fingers. The STTD coding is then decoded.

In addition, a decoupling circuit can be provided, by means of which the signals coupled in from different transmission antennas are decoupled. The functionality of this in 7 Decoupling circuit, not shown, can also be in the RAKE receiving circuit, for example 11 be implemented.

On the output side, the RAKE receive circuit 11 detected signal components via an MCR unit 17 a software facility 13 supplied, in which the estimated data signal d '(t) is determined. The software setup 13 that the hardware part 14 is connected downstream of the mobile radio receiver and contains the software, is typically designed as a digital signal processor (DSP).

About the connection 18 between the RAKE receiving circuit 11 and the AFC unit 15 the demodulated CPICH symbols are transmitted. Between the RAKE receiving circuit 11 and the software part 16 is an AFC unit according to the invention 15 provided, the structure and operation of which are based on the block diagram in 8th is described in more detail. The AFC unit generates control data e '''(t), which is the control part of the unit 13 are fed.

ausführlich dargelegt. Das berechnete Endergebnis kann anschließend über den Integrationspufferspeicher 22 dem Softwareteil des Mobilfunkempfängers zugeführt werden.The AFC unit 15 contains one of the RAKE receiving circuit 11 downstream input buffer memory 20 , for example a CPICH buffer memory, for buffering the received input data e '' (t). The input buffer 20 is a calculation circuit 21 downstream, in which phasors with the properties already mentioned are formed by multiplying STTD-decoded symbol pairs. Before the multiplication, the conjugate complex symbol pair is formed from one of the STTD-decoded symbol pairs. From an even number of adjacent phasors calculated in this way, an intermediate result is calculated by summation and is stored in the downstream integration buffer memory 22 is filed. The integration buffer 22 is designed for example as RAM (Read Access Memory). The integration buffer 22 is via a bidirectional data line with the calculation circuit 21 connected so that from in the integration memory 22 stored intermediate results the final results A can be calculated. The calculation algorithm used for this, which is in the calculation circuit 21 for example by means of a hard-wired logic circuit was implemented by the equation already described above

spelled out in detail. The calculated final result can then be stored in the integration buffer 22 be supplied to the software part of the mobile radio receiver.

The AFC unit 15 also contains one of the RAKE receiving circuit 11 downstream FSM unit 23 and AFC register unit 24 , FSM unit 23 and AFC register unit 24 are coupled to one another via a bidirectionally operable read / write line. The AFC register unit 24 contains parameter information, for example about which finger the RAKE reception scarf is tung 11 to which group belongs, as well as other configuration data.

The FSM unit 23 includes a sequence control circuit 25 to control the calculation circuit 21 , The sequence control also includes an additional functionality in symbol processing, by means of which a smaller number of phasors can also be used in the area of the frame boundary (group or cell-specific) to form an intermediate result by accumulation. This additional functionality goes out 5 out. The FSM unit also includes 23 advantageously also a counter 26 , by means of which the exact position within a UMTS frame (group or cell specific) can be determined. Sequencer circuit 25 and counter 26 are in hard-wired logic in the FSM unit 23 implemented for each group or cell separately or time-multiplexed.

• – Bei einer Änderung kritischer Parameter, zum Beispiel Modus- oder Offset-Änderung innerhalb einer Gruppe, erfolgt ein Stop der Akkumulation für diese Gruppe durch den Signalprozessor 13. Der Akkumulationszähler wird zurückgesetzt. Die im Zwischenspeicher 20 abgelegten Daten werden für alle RAKE-Finger dieser Gruppe gelöscht. Der im Zwischenspeicher 22 dieser Gruppe abgelegten Daten werden ebenfalls gelöscht.
• – Im Falle einer Kurzzeitakkumulation wird für die nächste anstehende Akkumulation die Skalierung hochgesetzt.
• – Die Akkumulation wird neu gestartet, sofern die Bedingungen für den Neustart einer Akkumulation erfüllt sind.

The functionality of the sequence control circuit according to the invention is described below 25 based on 8th described in detail. The sequence control circuit 25 within the FSM unit 23 As already mentioned, includes a preparatory phase, a data processing phase and a postprocessing phase:
In the preparation phase, the following procedural steps take place for each group of the signal paths organized in groups:

• - If critical parameters change, for example mode or offset changes within a group, the accumulation for this group is stopped by the signal processor 13 , The accumulation counter is reset. The one in the cache 20 stored data will be deleted for all RAKE fingers in this group. The one in the clipboard 22 data stored in this group will also be deleted.
• - In the case of a short-term accumulation, the scaling is increased for the next accumulation.
• - The accumulation is restarted if the conditions for restarting an accumulation are met.

• – Bei dem Normal-Modus der Gruppe eines RAKE-Fingers wird das Datum an entsprechender Stelle im CPICH-Pufferspeicher 20 gespeichert.
• – Im STTD-Modus der Gruppe eines RAKE-Fingers und gerader Symbolnummer erfolgt eine Speicherung des Datums an entsprechender Stelle im CPICH-Pufferspeicher 20.
• – Bei aktiviertem RAKE-Finger, aktivierter Akkumulation und Normal-Modus oder STTD-Modus und ungerader Symbolnummer erfolgen die folgenden Schritte: Lesen der beiden Werte für die Produktbildung aus dem CPICH-Pufferspeicher 20, Phasorberechnung, Lesen des bisherigen Integrationswertes der Gruppe aus dem Zwischenspei cher 22, Addition und Speicherung Zwischenspeicher 22. Diese Verfahrensschritte werden im STTD-Modus jeweils für jede Antenne getrennt durchgeführt.

In the data processing phase, the following process steps take place for each group based on the data of each RAKE finger:

• - In the normal mode of the group of a RAKE finger, the date is stored in the appropriate place in the CPICH buffer memory 20 saved.
• - In the STTD mode of the group of a RAKE finger and an even symbol number, the date is saved at the appropriate place in the CPICH buffer memory 20 ,
• - With activated RAKE finger, activated accumulation and normal mode or STTD mode and odd symbol number, the following steps are carried out: Reading the two values for the product formation from the CPICH buffer memory 20 , Phasor calculation, reading the previous integration value of the group from the buffer 22 , Addition and storage buffer 22 , These process steps are carried out separately for each antenna in STTD mode.

• – Bei laufender Akkumulation wird der Akkumulationszähler 26 erhöht.
• – Bei abgeschlossener Akkumulation wird ein Flag gesetzt für den Inhalt für „Zwischenspeicher enthält gültiges Ergebnis". Wechseln des aktuellen Zwischenspeichers 22 auf einen Schattenspeicher, da das Zwischenergebnis nicht überschrieben werden darf. Rücksetzen des Akkumulationszählers 26.
• – Bei einer Detektion des Frame-Endes wird der Inhalt des CPICH-Pufferspeichers 20 für alle RAKE-Finger dieser Gruppe gelöscht. Die Akkumulation wird gestoppt und der Startzeitpunkt für den Beginn der Akkumulation im neuen Frame wird gesetzt.
• – Bei einer Detektion des Frame-Endes und Kurzzeitakkumulation wird die Skalierung für diese Gruppe wieder auf den normalen Wert zurückgesetzt.
• – Bei einer Detektion einer Slot-Grenze des Referenzzählers 26 erfolgt ein Transfer aller fertiggestellten, d.h. gültigen Akkumulationen an den Signalprozessor 13. Der Inhalt des entsprechenden Zwischenspeichers 22 wird nach der Übertragung gelöscht. Rücksetzen der entsprechenden Flags auf „Ergebnis nicht gültig".

In the follow-up phase, the following procedural steps take place for each group of the signal paths organized in groups:

• - With accumulation running, the accumulation counter 26 elevated.
• - When the accumulation is complete, a flag is set for the content for "buffer contains valid result". Change of the current buffer 22 to a shadow memory, since the intermediate result must not be overwritten. Reset the accumulation counter 26 ,
• - When the frame end is detected, the content of the CPICH buffer memory 20 deleted for all RAKE fingers in this group. The accumulation is stopped and the start time for the start of the accumulation in the new frame is set.
• - Upon detection of the frame end and short-term accumulation, the scaling for this group is reset to the normal value.
• - When a slot limit of the reference counter is detected 26 there is a transfer of all completed, ie valid accumulations to the signal processor 13 , The content of the corresponding cache 22 will be deleted after the transfer. Resetting the corresponding flags to "result not valid".

9 shows a table from the example of the operation of the sequence control circuit according to the invention in a summarized representation 25 or FSM unit 23 out 8th evident. In the immediate vicinity of the end of the frame, the accumulation length is shortened from 4 phasors to 2 phasors according to the example in 5 performed. The example in 9 has been given for both D = 1 and D = 2. At the beginning of a frame, there is a wait until a corresponding number of phasors are available for the accumulation. At the end, a switch is made to a shortened accumulation. The last pairs of symbols for which accumulation is no longer possible or is not provided are no longer used for the calculation.

In the examples above, a coded UMTS signal was assumed in each case. These signals are sent and received on a frame basis, with a frame of 150 sym bolen, a slot consists of 10 symbols and each symbol consists of 256 digital individual signals (chips). However, the invention is not limited to such a coding, but can of course also be used for any other division of a frame.

The inventive method or the device according to the invention can preferably be used in a third generation mobile radio system, for example a UMTS system, which according to CDMA, TDMA, FDMA, etc. works. However, the invention is of course also can be used very advantageously with mobile radio systems of any other Generations, for example also with a GSM mobile radio system or GSM receiver

In summary it can be stated that by the design as described Procedure on very simple, but nevertheless very elegant Way caused by measurement falsification disturbance terms as well as temporally shifted signal paths of different Base stations are largely eliminated.

The The present invention has been accomplished based on the foregoing description so represented the principle of the method according to the invention and its practical Use as best as possible to explain, however leaves the invention with a suitable modification of course in realize diverse variants.

1

mobile system

2

base station

3

Channel

4

physical channel

5

receiver

6

mobile OPERATOR

10

receiving antenna

11

RAKE receiver circuit

12

delay means

13

Software Setup

14

hardware part

15

AFC unit

16

software part

20

Input buffer

21

calculation circuit

22

Integration buffer cache

23

FSM unit

24

AFC register unit

25

Sequencer circuit

26

(Reference-, Accumulation) counter

d (t)

data stream

s (t)

send signal

e (t)

receive signal

e '(t)

receive signal

e '' (t)

input data

e '' '(t)

control data

d '(t)

estimated data stream

Claims (27)

Method for preprocessing coded pilot channel signals in a mobile radio receiver ( 5 ), in which a reception-side separation of at least two from one transmitter ( 3 ) of a mobile radio system ( 1 ) transmitted, coded signals (s (t)), which can be used for pilot channel paths 4 ) in the form of frames, each with a fixed number of symbols, in which a frequency error estimate of the received signals (e (t)) is carried out, symbol pairs being formed by decoding two symbols adjacent to one another within a frame, in order to determine a frequency error neighboring symbol pairs are multiplied after formation of the conjugate complex value of one of the symbol pairs and the phasors obtained in this way are summed up to form an intermediate result, and an even number of phasors per receiver path are summed up to eliminate a disturbance when calculating the intermediate result. Method according to one of the preceding claims, characterized in that, before the frequency error estimate, the transmitted signals (s (t)) from a mobile radio receiver ( 5 ) received and separated from each other. Method according to one of the preceding claims, characterized characterized in that the coded signals (s (t)) are orthogonal to each other are TxDiv-modulated, in particular STTD-modulated. Method according to one of the preceding claims, characterized in that the intermediate result A is calculated by summation as follows:

where M denotes the number of signal paths within a group, P the symbols or symbol pairs of a pilot channel, the index m the respective signal path, the indices i, iD the sequence of the received symbol pairs or symbols, j the selection of an antenna , where D indicates the respective integration mode, a indicates which symbol within a frame with the Be calculation was started, and e + 1 shows the number of phasors used to determine the intermediate result. Method according to one of the preceding claims, characterized characterized that a calculation of intermediate results using Symbol sequences that are over extend the frame boundary, not done. Method according to one of the preceding claims, characterized characterized that depending on the completion of the last complete interim result with the full number of phasors before the end of a frame further intermediate result through accumulation over a smaller number of Phasors is formed. A method according to claim 6, characterized in that for a complete accumulation length a shorter one of 8 or 4 phasors Accumulation length over 4 or 2 phasors is provided. Method according to one of claims 6 or 7, characterized in that that the shorter one accumulation length by scaling to the order of magnitude complete accumulation length is adjusted. Method according to one of the preceding claims, characterized characterized that already with the calculation of the interim results is started within a frame. Method according to one of the preceding claims, characterized in that a plurality of delay devices ( 12 ) a RAKE receiver unit ( 11 ) are organized in groups and by the grouped delay devices ( 12 ) received signals are treated together, in particular are stored in a group-specific manner, and group-specific integration of intermediate results takes place. A method according to claim 10, characterized in that group-specific storage and group-specific Integration of intermediate results depending on group-specific Parameters and / or a time offset of the frame profiles of a each group is carried out on an externally generated reference time scale. Method according to one of claims 10 or 11, characterized in that that a delay in individual recipient paths balanced within each group by means of a reference time scale becomes. Method according to one of claims 10 to 12, characterized in that dependent of the time lag of the individual groups the calculation of the intermediate results to different Times in relation to the reference time scale is carried out. Method according to one of claims 10 to 13, characterized in that that dependent from the index of the symbol within the frame history belonging to a group after the completion of the last complete interim result with the full number of phasors before the end of a frame further intermediate result for accumulation over a smaller number of Phasors is formed. Method according to one of the preceding claims, characterized in that the signal parts from different transmitters ( 3 ) of a mobile radio system ( 1 ) transmitted signals are separated from each other before the frequency error estimation. Method according to one of the preceding claims, characterized characterized in that a sequence control for at least one data path is provided, the sequence control being divided into the following phases is: - data preparation, - data processing, while the data of each delay device group-specific to integrate interim results, - post-processing, in which the phases of data preparation and post-processing include parameter management as well as control and switching operations includes. Method according to one of the preceding claims, characterized characterized that different temporal offsets of the frame course recognized and processed between different groups. Method according to one of the preceding claims, characterized characterized in that activation of the control mechanisms for decoding, in particular for one STTD decoding, from transmission mode depends on the respective group. Mobile radio receiver ( 5 ), in particular for carrying out a method according to one of the preceding claims, with a receiving device ( 10 ) for receiving a via a transmission channel ( 4 ) from a base station ( 2 ) transmitted signal (e (t)), one of the receiving device ( 10 ) downstream RAKE receiver unit ( 11 ) with several delay devices connected in parallel ( 12 ) for the detection of the different signal paths ( 4 ) transmitted signal components of the transmitted th signal (e (t)), an AFC circuit ( 15 ) for automatic frequency correction and combining means ( 13 ) for assembling the signal components into an estimated received signal (d '(t)). Mobile radio receiver according to claim 19, characterized in that a plurality of delay devices ( 12 ) a receiving unit ( 11 ) are grouped and organized in such a way that this group handles the received data and signals together. Mobile radio receiver according to one of claims 19 or 20, characterized in that several groups of the same base station ( 2 ) assigned. Mobile radio receiver according to claim 21, characterized in that as a criterion for a grouping of several delay devices ( 12 ) to a group of the same base station ( 2 ) whose affiliation to the signal paths of the same base station is with a uniform frame course. Mobile radio receiver according to one of claims 19 to 22, characterized in that the AFC circuit ( 15 ) a sequence control circuit ( 25 ) contains, which in a hardware part ( 14 ) of the mobile radio receiver ( 5 ) is arranged and via which preprocessing can be carried out during the accumulation and at the end of a frame. Mobile radio receiver according to one of claims 19 to 23, characterized in that a sequence control circuit ( 25 ) in a hardware part ( 14 ) of the mobile radio receiver ( 5 ) is provided, the individual processing steps for the received signals of the delay devices ( 12 ) group-specific in a buffer device ( 22 ) saves. Mobile radio receiver according to one of claims 23 or 24, characterized in that the sequence control circuit ( 25 ) is designed as a hardware circuit, in particular as a hard-wired logic circuit. Mobile radio receiver according to one of Claims 19 to 25, characterized in that a reference counter ( 26 ), in particular a reference counter working in groups ( 26 ) is provided, via the counter reading of which the exact position can be determined within a frame. Mobile radio receiver according to one of claims 19 to 26, characterized in that an input buffer ( 20 ) is provided, which of the receiving device ( 10 ) is connected downstream and buffers the received data.