Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
  • H04W52/04—TPC
  • H04W52/54—Signalisation aspects of the TPC commands, e.g. frame structure
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
  • H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
  • H04B7/2643—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA]
  • H04B7/2656—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA] for structure of frame, burst
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W56/00—Synchronisation arrangements
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W24/00—Supervisory, monitoring or testing arrangements

Definitions

• the invention relates to a method for transmission control in a radio communication system, in particular a method and a radio communication system for controlling synchronization and / or transmission power in a radio communication system.
• radio communication systems for example the European second generation mobile radio system GSM (Global System for Mobile Communications)
• information for example voice, image information or other data
• the radio interface relates to a connection between a base station (NB - Node B) and subscriber stations (UE - User Equipment), the subscriber stations being, for example, mobile stations or fixed
• the electromagnetic waves are emitted at carrier frequencies that lie in a frequency band provided for the respective system.
• frequencies in the frequency band of approx. 2000 MHz are provided.
• Two modes are provided for the third mobile radio generation, one mode denoting FDD operation (frequency division duplex) and the other mode denoting TDD operation (time division duplex). These modes are used in different frequency bands. Both modes support a so-called CDMA subscriber separation procedure (Code Division Multiple
• the TDD mode is in a high data rate mode, the so-called high
• Chip rate option with 3.84 Mcps, and divided into a low bit rate mode, the so-called low chip rate option (TDD-LCR) with 1.28 Mcps.
• the structure of the transmission layer of the low chip rate option is closely based on the TD-SCDMA system standardized in China by the CWTS.
• the 1.28 Mcps option of the UMTS-TDD standard is used both for synchronization of the transmission in the uplink (UL), i.e. from subscriber stations to the
• Base station as well as a fast signaling on the physical transmission layer (layer 1 of the ISO / OSI layer model) for transmit power control. For example, in the case of transmissions of the base station in the downward direction.
• Downlink, DL) to subscriber stations so-called SS (Synchronization Shift) and TPC (Transmit Power Control) commands are integrated, which influence subsequent transmissions of the subscriber stations with regard to synchronization and transmission power.
• SS Synchronization Shift
• TPC Transmit Power Control
• Command SSI in each subframe the timing for the uplink time slot ULI, and command SS2 always the timing for the uplink time slot UL2.
• a code used for the transmission in the downward direction can also be temporarily switched off, which transmits SS and TPC commands for the subscriber station UE.
• the synchronization and / or the transmission power control of the transmission in the corresponding uplink time slot is not controlled for the same period of time until, for example, the data rate in the downlink time slot rises again and the corresponding code is activated again, which in turn activates the contains corresponding commands or control information for the uplink time slot.
• the object of the invention is therefore to provide a method that enables secure transmission of commands in the aforementioned situations. This object is achieved by the method according to the features of patent claim 1. Advantageous developments of the invention can be found in the dependent claims.
• FIG. 1 shows a block diagram of a radio communication system
• FIG 3 shows a sequence of subframes with an example
• FIG. 7 shows a table with the assignment of commands to uplink time slots according to the prior art
• FIG. 8 shows a table with the assignment of commands
• a mobile radio system consists of a large number of mobile switching centers (MSC - Mobile Switching Center), which belong to a switching network (SSS - Switching Subsystem) and are networked with one another or provide access to a fixed network (PSTN - Public Switched Telephone Network) , and one or more base station systems (BSS - Base Station Subsystem) connected to these mobile switching centers.
• MSC mobile switching centers
• SSS Switching Subsystem
• PSTN Public Switched Telephone Network
• BSS Base Station Subsystem
• a base station system in turn has at least one device for assigning radio resources (RNC - Radio Network Controller) and at least one base station NB (node B) connected to it.
• RNC Radio Network Controller
• a base station NB can establish and trigger connections to subscriber stations UE (user equipment) via a radio interface. At least one radio cell is formed by each base station NB. The size of the radio cell is generally determined by the range of a general signaling channel that is transmitted by the base stations NB with a constant transmission power. In the case of sectorization or hierarchical cell structures, several radio cells Z can also be supplied per base station NB. The functionality of this structure can be transferred to other radio communication systems in which the invention can be used.
• FIG. 1 shows subscriber stations UE1, UE2 which are located in the radio cell of a base station NB.
• the subscriber stations UE1, UE2 have established communication connections to the base station NB on which a signal transmission of one or more signals in the upward UL and downward direction DL selected services.
• the communication connections are separated by one or more spreading codes and / or time slots allocated to the respective subscriber station from communication connections established in parallel in the radio cell.
• the rigid mapping described above of a downlink time slot transmitting a command to a corresponding uplink time slot is replaced by a randomly controlled and thus dynamic mapping.
• the commands are assigned in downlink time slots in such a way that the corresponding control commands in the downlink time slots are assigned to the uplink time slots as evenly as possible.
• the assignment of the control commands SSI, SS2 to the uplink time slots ULI, UL2 is exchanged for this in each odd subframe, and an equal distribution of the error probability due to the diversity obtained is thereby achieved.
• both uplink time slots ULI, UL2 are also by corresponding commands SSI and SS2, which alternate in the first downlink time slot are transmitted, controllable with respect to the synchronization.
• TPC transmission power control commands
• FIG. 7 shows an example of the assignment of three commands SSI, SS2, SS3 to three uplink time slots ULI, UL2, UL3 in accordance with the method defined in the standard. If the case occurs that the transmission of the command SS3 is interrupted, for example due to rate matching, it is not possible to control the synchronization of the third uplink time slot UL3.
• FIG. 6 shows, by way of example, a sequence of the distribution of the synchronization commands (Received SS command #) received by the subscriber station to the uplink time slots to be controlled (Controlled UL TS #) as a function of the system time frame number (SFN - system) Frame number).
• SFN - system system time frame number
• VL pos ⁇ SFN'-N SSsymbols + SS pos ) mod (N ULslot )
• the uplink time slots 1 and 3 are not controlled if the command SS 1 is not transmitted or received, for example due to rate matching.
• this disadvantageous loss of control does not occur.
• the above formula for the dynamic distribution also advantageously allows the largest interval between two control periods of an uplink to be minimized.
• Time slot The length of the interval depends on the relationship between the number of commands and the time slots to be checked. In the event that an equal number of commands and time slots to be checked exist, control takes place in each subframe.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Mobile Radio Communication Systems (AREA)
• Small-Scale Networks (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=30775288

Family Applications (1)

Country Status (5)

Cited By (6)

Families Citing this family (2)

Citations (4)

Family Cites Families (1)

• 2002
  • 2002-08-14 DE DE2002137330 patent/DE10237330A1/de not_active Withdrawn
• 2003
  • 2003-08-11 AU AU2003266118A patent/AU2003266118A1/en not_active Abandoned
  • 2003-08-11 WO PCT/DE2003/002696 patent/WO2004021607A1/de not_active Application Discontinuation
  • 2003-08-11 RU RU2005106878/09A patent/RU2328076C2/ru not_active IP Right Cessation
  • 2003-08-11 CN CN03819489.9A patent/CN1675860B/zh not_active Expired - Lifetime

Patent Citations (5)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events