DE19932455A1 - Transmission structure update and/or adjustment in communication system - Google Patents

Abstract

The method involves updating and/or adjusting transmission structures of a communication system, especially a radio communications system with an interface between at least one of, especially several first stations (BS) and at least one of, especially several further stations (M). Respectively at least one first station is connected over the interface (V1 - V3) with several further stations, and data are transmitted according to the standards of at least one fixed transmission structure which is updated and/or adjusted over the communication system. A transmission frame time slot structure is preferably used as transmission structure, especially in the up- and/or downlink.

Description

The invention relates to a method for updating and / or adaptation of transmission structures, in particular Time slot structures according to the generic features of claim 1 and a communication system for order put this procedure.

In radio communication systems, information (at for example, language, image information or other data) Using electromagnetic waves over a radio cut position between the sending and receiving station (base station tion or subscriber station). The blasting of the electromagnetic waves occur with carrier-free sequences that are provided for the respective system Frequency band. For future mobile radio systems with CDMA or TD / CDMA radio transmission methods interface, for example the UMTS (Universal Mobile Telecommunication System) or other 3rd generation systems tion are frequencies in the frequency band of approx. 2000 MHz see.

In mobile radio systems are used for the transmission of data and for signaling the data structures through specifications as specified for the GSM Rec. or DECT Rec. This Data structures such as number of time slots, Time slot frame, duration of the time slots and time slot frame and the burst structures for TDMA, TDD, TD / CDMA, TD / SDCDMA and FDD systems and spreading codes for CDMA systems must then in base stations communicating with each other and mobile station can be implemented.  

Change over the life of such mobile radio systems the requirements for such structures or there will be improved structures developed. Such changed structure However, structures cannot be implemented quickly because the specifications only changed and also in the standard bodies like ETSI, ITU or ARIB must be coordinated. Such change requests can be very tedious.

It is common for the data block or burst structures to be defined, for example in GSM, where a time slot frame consists of 8 time slots, as shown in FIG. 1. A single time slot has a duration of 0.577 msec and the entire time slot frame has a duration of approximately 4.6 msec. Furthermore, multi-frames or multi-frames for data and signaling as well as superordinate super frames and hyperframes are defined.

Furthermore, various types of bursts such as, for example, normal burst, frequency correction burst (frequency correction burst), synchronization burst, placeholder or dummy burst and access or access burst are clearly defined. The normal burst shown in FIG. 2, which is used for the transmission of data for signaling, is specified in accordance with the following Table 1:

Table 1

well-known GSM normal burst

Here are the 8 possible training sequences as well as the tail Bit or list end markings through the specifications clearly defined and thus also the performance or performance.

In the DECT system, the structures of the time slots and the corresponding data blocks or bursts for full-time slot (Full slot), half-time slot (half slot) and double time slot (double slot) methods clearly defined.

In order for a mobile radio system or other transmission systems to create a new burst structure or time slot structure throw, complex simulations are necessary to get the Define structures and then standardize them. This means that standardization and Development of a new cellular standard takes a lot of time needed.

For example, in an existing cellular network new service will be introduced, for example for Optimizing the transmission rate another time slot structure and / or burst structure for TDMA / TDD-, TD / CDMA-, TD / SDCDMA systems and / or other spreading codes for pure CDMA Systems or FDMA / TDMA / CDMA systems than those previously in the system should have implemented structures. In this case  mobile subscribers usually have a new handset with them be made available to this new feature.

It can also occur during the active operation of the network exhibit that the specified structures in certain Scenarios do not have the required performance provide. Then new structures have to be specified and these into the network elements such as the base stations and will implement the mobile stations.

The invention is based on the object, method and radio To provide communication systems in which transm supply structures, in particular time slot structures without a high level of technical effort, particularly for base station tions and mobile stations updated and newly set up can be.

This task is accomplished through the update procedure and / or adaptation of transmission structures, in particular Time slot structures with the features of claim 1 and the communication system with the features of claim 16 solved.

Updating transmission structures, in particular Time slot structures made possible via the communication system light a very variable and quick adjustment of the individual Facilities of the communication system, especially the End stations and the stations communicating with them.

Advantageous further developments are the subject of Unteran sayings.

Only when requesting a service from a communicating Station the special time slot structure and the structure of the physical content (burst) of the time slot  sharing allows you to provide a simple reason transmission framework, which can be supplemented in a particularly variable manner. The burst structures can, however, also have a BCCH be sent.

The fixed definition is particularly advantageous only the reason structure, such as a time slot frame (TDMA- Frame), so that the individual time slot structures and Burst types are then defined for the different services can be, if the services are fixed on their own.

The transfer and adaptation of the structures is advantageous via software or information elements via the network for the Base stations and over the air interfaces for the be meeting mobile stations. The structures can also be dependent on service.

The storage of various transmission structures via a definable or fixed period in one Memory in the handset (MS) and / or the base stations (BS) on the one hand, does not allow for every connection establishment required transfer of the parameters of the corresponding Transfer structure. On the other hand, the storage opt selection of transmission to be saved structures and / or the deletion of a predefinable Period of unused transmission structures and / or relatively rarely used transmission structures from the Storage suggested.

A basic time slot procedure and basic error protection procedures for transferring the parameters set a be particularly efficient and safe adaptation of the transmission structure to the requested service.  

Data structures such as the number of time slots, Timeslot frame, duration of timeslots and time slot frame and the burst structures for TDMA, TDD, TD / CDMA, TD / SDCDMA and FDD systems as well as spreading codes for CDMA systems are thus in communicating with each other Base stations and mobile station implemented.

An exemplary embodiment is described below with reference to the drawing explained in more detail. Show it:

Fig. 1 data frame of the prior art,

Fig. 2 shows a known normal burst as part of a multi-frame,

Fig. 3 is a block diagram of a known mobile radio system,

Fig. 4 is a schematic representation of the known frame structure of the TDD transmission method and

Fig. 5 shows a specially adapted burst.

The mobile radio system shown in FIG. 3 as an example of a known radio communication system consists of a large number of base station control devices or mobile switching centers MSC, which are networked with one another or provide access to a fixed network PSTN. Furthermore, these mobile switching centers MSC are each connected to at least one device RNM for allocating radio resources. Each of these RNM facilities in turn enables a connection to at least one base station BS. Such a base station BS can connect to subscriber stations, e.g. B. Mobile stations MS or other mobile and stationary devices. At least one radio cell Z is formed by each base station BS. In the case of sectorization or hierarchical cell structures, several radio cells Z are also supplied per base station BS.

In FIG. 3, by way of example, existing connections V1, V2, V3 for transmitting user information and Signalisie changed information between mobile stations MS and a base station BS and a request for resource allocation or a short acknowledgment message in an access channel RACH and by another mobile station MS. Furthermore, an organization channel (BCCH: Broadcast Control CHannel) is shown, which is provided for the transmission of user and signaling information with a defined transmission power from each of the base stations (BS) for all mobile stations.

An operation and maintenance center OMC realizes control and maintenance functions for the mobile radio system or for parts from that. The functionality of this structure is different Radio communication systems transferable, especially for Subscriber access networks with wireless subscriber connection.

The frame structure of the radio transmission for TDMA / CDMA can be seen from FIG. 4. According to a TDMA component (TDMA: Time Division Multiple Access), a division of a broadband frequency range, for example the bandwidth B = 5 MHz, into a plurality of time slots ts of the same duration, for example 16 time slots ts0 to ts15, is provided. A frequency band extends over a frequency range B. Part of the time slots ts0 to ts8 is used in the downward direction DL (downlink from BS to MS) and part of the time slots ts9 to ts15 is used in the upward direction UL (uplink from MS to BS). In between are one or more switching points SP - only one switching point in FIG. 4. In this TDD transmission method, the frequency band for the upward direction UL corresponds to the frequency band for the downward direction DL. The same is repeated for other carrier frequencies.

Information within the time slots ts is more than one Transfer connections in radio blocks. Radio blocks for use Data transmission consist of sections with data d, in training sequences known to those on the receiving side until one are embedded. The data d with 1. . N symbols are ver binding-specific with a fine structure, a participant Merkode c, spread so that, for example, n Connections through this CDMA component (CDMA: Code Division Multiple Access) can be separated. A physical channel is thereby by a frequency band B, a time slot, for. B. ts6, and a subscriber code c formed. For the transfer of Services with high data rates are usually several physical resources linked to a logical channel. For example, 144 kbit / s in uplink and Downlink requires 8 physical resources each.

The spread of individual symbols of the data d causes that within the symbol duration Tsym Q chips the duration Tchip over will wear. The Q chips form the connection individual participant code c. Furthermore, within the Time slot ts a guard time gp (guard period) for Compensation of different signal transit times of the signals of connections provided.

The UMTS / TDD radio interface parameters used are advantageously:
Chip rate: 3.84 Mcps
Frame duration: 10 ms
Number of time slots: 15
Duration of a time slot: 666 µs
Spread factor: 16
Modulation type: QPSK
Bandwidth: 5 MHz
Repeat frequency value: 1

These parameters also enable a particularly suitable one Harmonization with an FDD mode (FDD: Frequency Division Duplex) for the 3rd generation of mobile communications.

In TDD mode, the individual distinction is made given by an appropriately assigned spreading code c. A mobile station MS that wants to establish a connection receives in on your request sent via the BACH known way u. a. the information which spread code c is to be used for access or connection establishment.

According to the present embodiment is in the one directions of the communication system advantageously just a basic structure of a general purpose Transmission frame provided.

If a subscriber demands a certain one Service, then a corresponding service belongs to this service special time slot structure. This time slot structure is essentially by the starting point and the duration of the Time slot and the associated data block or burst structure marked. At the Service request according to the individual parameters of the time slot structures communicated.

With this information, the air interface between rule a mobile station MS and a base station BS for the special requested service with the appropriate para of the time slots. In addition, the Other parameters are also transmitted to the participants, such as the transmission power, a spreading code c etc.

Saving different ones is particularly advantageous Transmission structures over a longer period in one Memory in the handset MS and in particular the base stations  BS, so that not every time you connect first Training or coordination with the transfer of all required data, e.g. B. beyond the basic frame go, and conditioning performed by these must become. It will be announced in particular where the burst should start and end. One can such information u. a. also broadcast on the BCCH, which constantly communicates which ones Bit of the basic frame are occupied.

Appropriately, there is in particular the mobile stations MS selected only certain transmission save structures. Alternatively or in addition to Memory optimization also implement an automatic function animal that is not used for a given period of time Transmission structures or relatively rarely used over deletes structures from the memory.

After submitting a suitable transfer Structure or selection of these from the memory are in Handset implemented burst installation facilities and Burst uninstallation facilities with the corresponding Parameters supplied.

The handset thus only serves as one Hardware platform.

So that the parameters of the time slot structures are secured over the network elements, especially the Mobile stations MS and the base stations BS have a base time slot procedure and a basic error protection procedure for Transfer the parameters to. For example, can be used have an ARQ (Automatic Repeat Request) method that is based on a block code, and in terms of the time slot Structure of the normal burst of the GSM system.  

Furthermore, according to a particularly advantageous embodiment form also changed tail bit or list end markings and / or training sequences with improved performance ability to be transferred. To increase the data rate can e.g. B. also shortened tail bit and shortened training sequences can be selected.

In this method, a wide variety of known and Burst types to be developed in the future can be used. Examples are access bursts for random access (random Access) or a handover access, Fre Frequency Correction Bursts, Syn chronization bursts, normal bursts for voice, data, Signaling and broadcasting as well as placeholder or Dummy bursts.

An exemplary structure of a normal burst for an existing time slot with a duration of 0.577 msec, which enables such an adaptation to different services and has shortened tail bits and training sequences, is shown in FIG. 5 and Table 2:

Table 2

Structure of a burst with a shortened tail bit and a shortened training sequence

This exemplary normal burst contains the shortened Tail bit and the shortened training sequence approx. 20% more Data bit.

According to another exemplary embodiment also the possibility of shortened normal burst for lower Introduce data rates when, for example, a new language  codec can be realized with a very low data rate should.

To transfer the special parameters of the normal burst and the bit sequence for the tail bit and the bit sequence of the Training sequence can be according to a particularly advantageous Embodiment a messaging service can be used as e.g. B. the well-known short message service SMS. In addition, the The time or starting point of the time slot is communicated to who the. But also transmission channels like random access Channel FACH or the BCCH are for the transmission of this required information.

You can also use normal burst with two training sequences specified that are much longer and one higher performance or performance available put.

According to a particular embodiment, a is preferably used certain information element from a mobile station MS, which supports flexible structures, to the network or with this communicating base station BS sent so this and / or the system will recognize whether the communicating mobile station MS can work with flexible structures. That too additional information element is preferably during the Service request submitted. This information can in the home register HLR and / or visitor register VLR by the Set a flag to be saved. Alternatively, the Transmission of a corresponding information element too base stations BS working with flexible structures Mobile stations MS and / or the communication system take place, when new connections are established.

The transmission and adaptation are also particularly advantageous structure by software or transmission via  Information elements about the network for the base stations BS and via the air interfaces for the mobile in question stations MS. The structures can also be service-dependent his.

In general, the time slot structures can both in the uplink as well as in the downlink, whereby for the Downlink z. B. other burst structures can also be defined can.

Exemplary variants are described below using the be standing GSM system with a time slot frame from 8 Time slots listed. Each time slot has a duration of 0.577 msec or contains exactly 156.25 bits. Every bit has a bit duration of 3.69 µsec. So a time slot frame has 156.25 bits by 8 time slots, i. H. 1250 bits. This 1250 bit can e.g. B. remain as a basic structure.

If a subscriber requests a service, one can be given one assign the corresponding share from these 1250 bits, whereby here it should be assumed that for a normal language service (service 1) including channel coding for example for full-rate speech, a gross data rate of 22.8 kbit / s (Burst 1) is required for a half-rate speech channel (Service 2) a gross data rate of 8.0 kbit / s (burst 2), for a 64 kbit / s data service (service 3) a gross data rate of 85.8 kbit / s (burst 3), for a 32 Kbit / s data service (Service 4) a gross data rate of 54.8 kbit / s (burst 4) and a gross data for a 16 Kbit / s data service (service 5) rate of 39.0 kbit / s (burst 5).

Then z. B. Data burst according to the following tables 3 to 7 can be defined, the sequence of fields again the sequence of the previous tables corresponds to:  

Table 3

Burst 1 (total bit 156)

Table 4

Burst 2 (total bit 78)

Table 5

Burst 3 (total bit 468)

Table 6

Burst 4 (total bit 312)

Table 7

Burst 5 (total bit 234)

The bits on the air interface are through from 1 to 1250 numbered as shown in Table 8. Requests Participant in service 1, the burst 1 is sent to him assigns with bits 1 to 156 of a time slot frame. Then a subscriber requests a service 2 bits 157 to 234 are assigned to it. Become For example, services 3, 4 and 5 continue in succession requested, then the next participant gets for the Service 3 burst 3 on bits 235 to 702, the subscriber then for service 4 (burst 4) bits 703 to 1014 and the following subscriber then for service 5 (burst 5) Bit 1015 to 1248. The remaining 2 bits remain free. On a different frequency it may look different, depending on what the participants supplied via it have requested.  

Table 8

Capacity distribution on the air interface

The participant is also included in a message shares with which bit of the time slot frame its burst begins and ends. He is also informed which one Structure of the burst.

Another constellation could e.g. B. consist in that twice service 3 and once service 4 is requested. The first subscriber from service 3 could use bits 1 to 468, the second subscriber from service 3 bits 469 to 936 and the Service 4 participants assigned bits 937 to 1248 become. The remaining 2 bits of the 1250 bits of the time slot frames remain free. This assignment is in the table 9 illustrates.

Table 9

twice service 3, once service 4

Table 10 shows another constellation of sixteen times service 2.

Table 10

service sixteen times

Yet another constellation is four times in Table 11 Service 5 and three times Service 2 shown.

Table 11

four times service 5, three times service 2

The structures on the individual frequencies can of course be different.

Claims (16)

1. Method for updating and / or adapting transmission structures in a communication system, in particular radio communication system with an interface between at least one, in particular a plurality of first stations (BS) and at least one, in particular a plurality of further stations (MS), in which

• - In each case at least one first station (BS) can be connected to several further stations (MS) via the interface (V1-V3) and
• data to be transmitted are transmitted in accordance with the requirements of at least one fixed transmission structure,

characterized in that

• - The at least one transmission structure can be transmitted and / or updated via the communication system.

2. The method according to claim 1, wherein a transmission frame time slot as the transmission structure structure is used, especially in up and / or down link. 3. The method according to claim 1 or 2, wherein the communication system is a mobile radio communication system with base stations (BS) and mobile stations (MS) and especially an operations and maintenance center (OMC) that communicate with each other via interfaces. 4. The method according to any one of the preceding claims, in which the transmission structure when a service is requested, in particular time slot structure and / or the structure of the phy sical content (burst) of the structure between the communicating stations are transmitted.   5. The method according to any one of the preceding claims, in which between communicating stations beginning and end of a Bursts or time slots for start and end in the downlink and / or uplink are announced. 6. The method according to any one of the preceding claims, in which without requesting a special service and / or for Establishing a connection using a base frame. 7. The method according to any one of the preceding claims, in which the transfer and / or adaptation of the structures via soft goods and / or via information elements via a commun cation network for base stations (BS) and via air cut places for mobile stations (MS). 8. The method according to any one of the preceding claims, in which the transmission structures are selected depending on the service. 9. The method according to any one of the preceding claims, in which different transmission structures over at least one definable or fixed period in a memory abge in mobile stations (MS) and / or base stations (BS) be saved. 10. The method according to claim 9, wherein selected transmission structures can be saved and / or not used for a predefinable period Transmission structures and / or relatively rarely used Transmission structures are deleted from the memory. 11. The method according to any one of the preceding claims, at a basic time slot procedure and basic error protection methods for transferring parameters can be used.   12. The method according to any one of the preceding claims, at which the transmission channel consists of one or more under different bursts, which in turn are different frequencies can be laid. 13. The method according to any one of the preceding claims, at a message for the transmission of special parameters service, especially short message service (SMS) used becomes. 14. The method according to any one of the preceding claims, at the first supporting flexible structures and / or other stations (BS, MS) signaled their ability is transmitted, in particular an information element. 15. The method according to any one of the preceding claims, at in the first and / or further stations (BS, MS), in Home register (HLR), in the visitor register (VLR) and / or a base station control device (MSC) in particular by setting a flag it is registered whether the commun ornamental stations (MS, BS) flexible structures under support. 16. Communication system, in particular radio communication system for implementing a method according to one of the preceding outgoing claims.