Classifications

• • 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
  • H04B7/2618—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using hybrid code-time division multiple access [CDMA-TDMA]
• • 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
  • H04W52/30—TPC using constraints in the total amount of available transmission power
  • H04W52/32—TPC of broadcast or control channels
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
  • H04W88/02—Terminal devices
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
  • H04W88/08—Access point devices

Definitions

• the invention relates to a base station and a receiving device for a mobile communication system with a TDMA component for subscriber separation, the receiving device being used particularly in mobile stations.
• GSM Global System for Mobile Radio system
• System for Mobile Communications is a mobile communication system with a TDMA component for subscriber separation (time division multiple access).
• TDMA component for subscriber separation (time division multiple access).
• user information of the subscriber connections is transmitted in time slots. The transmission takes place in blocks.
• channels BCCH broadcast control channel
• This organizational information includes information about the location area, the radio cell, the channel structure and options that are supported within the cell.
• a mobile communication system is known from DE 195 49 148.3 which uses CDMA subscriber separation (CDMA code division multiple access) and uses a JD method (joint detection) on the receiving side in order to be able to use Spreading codes of several participants to make an improved detection of the transmitted useful information.
• CDMA subscriber separation CDMA code division multiple access
• JD method joint detection
• the invention is based on the object of specifying a transmission of organizational information for a mobile communication system with TDMA subscriber separation, which enables economic recipient structures. This object is achieved by the base station with the features of claim 1 and the receiving device with the features of claim 12. Advantageous further developments can be found in the subclaims.
• a base station for a mobile communication system with TDMA subscriber separation contains a signal processing device for preparing useful information and organizational information for transmission via a radio interface.
• the signal processing device is controlled by a control device which prepares the useful information in blocks according to the TDMA subscriber separation in time slots and the organizational information for permanent wave transmission over more than one time slot.
• the useful information and the signals transmitting the organizational information are combined to form a transmission signal.
• the transmission signal is modulated for high-frequency radiation in a transmission device.
• TDMA time division multiple access
• power control can only be used for channels of the useful information, during which the organizational information is emitted with a constant transmission power.
• This organization channel with constant power can thus be used as a reference for power control and for handover information (measurements).
• optimized cell planning can be carried out for the channels of the useful information.
• the radio resources are used well for the useful information.
• the organizational information is always available. It is not necessary to synchronize base stations with one another.
• the useful information and organizational information are advantageously transmitted in the same frequency band and possibly the same bandwidth. This simplifies cell planning and makes better use of the radio resources available in a cell - the bandwidth.
• the permanent wave transmission advantageously extends over two or more time slots, for example all time slots which are available for transmission in the downward direction. The longer the perm transmission can continue, the greater the process gains that can be achieved.
• the signal processing device is designed in such a way that a CDMA method with individual spreading codes is additionally used for subscriber separation in a time slot.
• the user information thus becomes broadband, e.g. in a 1.6 or 2.0 MHz frequency band.
• Correct power control is particularly important in such mobile communication systems, since several subscriber signals are transmitted simultaneously in one frequency channel. Power fluctuations of the received subscriber signals are largely compensated for by the power control.
• a JD (joint detection) method is advantageously used for the detection of the subscriber signals. This allows the interference of other subscriber signals to be taken into account when detecting a subscriber signal.
• the organizational information is recorded using a DS-CDMA method spread by a spreading factor.
• a CDMA method " for transmission" is also selected for the organizational information, so that on the receiver side the signal processing device can use at least partially common components or algorithms for both CDMA methods.
• a larger spreading factor is advantageously used to spread the organizational information than to spread the useful information. This means a greater process gain for the organizational information than for the useful information.
• the channel for organizational information is therefore more interference-resistant.
• the larger spreading factor for the organizational information is achieved according to an advantageous embodiment in that symbols of the organizational information have a longer symbol duration than symbols of the useful information.
• the symbol duration of the organizational information can be an integral multiple of the useful information.
• the subscriber codes or chips representing DS-CDMA spreading sequences can be the same
• Chip length (or an integer multiple thereof).
• a common clock can consequently be used to generate the chips.
• the greater process gain for the organizational information is advantageously achieved in that a significantly lower data rate, for example less than or equal to 1 kbit / s, is used in comparison to the data rate of the useful information.
• the organizational information is therefore limited to the most essential information, which is, however, transmitted in a very interference-resistant manner.
• the signal processing device is designed in such a way that signaling information is prepared for block-wise transmission in the time slots. So it will be a TDMA based Procedures for the signaling information applied.
• This signaling information is " possibly individualized like the useful information, so that power regulation is advantageous.
• a separate spreading code is expediently used for the signaling information and the frequency channel of the useful information is used. The combination and separation of the useful and signaling information can thus be pure computationally, without additional circuitry.
• the separate treatment of user information and organizational information is particularly advantageous if directional radiation (e.g. using adaptive antennas) is possible with an antenna device assigned to the base station.
• the user information is directed and the organizational information is omnidirectional or sectoral, with less antenna gain than for the directed radiation.
• the directional effect of the antennas can be used to achieve greater ranges for the useful information.
• the greater process gain also extends the reach for organizational information. If the useful information and the organizational information are emitted with approximately the same power, the transmission device is simplified in structure; nevertheless, a comparable range for useful information and organizational information can be achieved according to the above expression.
• 1 shows a block diagram of a mobile radio network
• 2 shows a schematic representation of the frame structure of the radio interface
• FIG. 3 shows a block diagram of a transmission device of a base station
• FIG. 4 shows a block diagram of a receiving device of a mobile station.
• the structure of the mobile communication system shown in FIG. 1 corresponds to a known GSM mobile radio network which consists of a multiplicity of mobile switching centers MSC which are networked with one another or which provide access to a fixed network PSTN. Furthermore, these mobile switching centers MSC are each connected to at least one base station controller BSC. Each base station controller BSC in turn enables a connection to at least one base station BS.
• a base station BS is a radio station which can set up a message connection to mobile stations MS via a radio interface.
• An operation and maintenance center OMC implements control and maintenance functions for the cellular network or for parts of it.
• the functionality of this structure can be transferred to other mobile communication systems in which the invention can be used.
• the base station BS is connected to an antenna device AE which, for example, consists of three individual radiators. Each of the individual radiators radiates in a sector of the radio cell supplied by the base station BS. Alternatively, however, a larger number of individual steel workers (according to adaptive antennas) can be used, so that a spatial
• the spreading factor defined by the number of chips per data symbol, being denoted by Ql to Q8.
• the spreading factor Q1 of the first subscriber signal is, for example, three.
• the spreading code cl is repeated from data symbol d to data symbol d.
• the spreading of the signaling information si takes place in accordance with the spreading of the useful information ni.
• the spreading of the data oid of the organizational information oi takes place according to a DS-CDMA method, the symbol duration of one of these data symbols being significantly longer than that of the data d of the useful information ni.
• the length of the chips for spreading the useful information ni and the organizational information oi is the same.
• the data rate of the organizational information oi is, for example, 200 bit / s, during which the useful information ni is transmitted at a data rate of 16 kbit / s in the case of voice transmission. 2 the ratio of the spreading factors Q1 to Q9 is therefore not given to scale.
• the transmitting device contains a signal processing device SP, for example a digital signal processor, which is controlled by a control device SE. Furthermore, the transmission device contains a combination device MUX for combining the signals of the useful information ni, the signaling information si and the co o M P- P-
• the RAKE receiver RAKE measures the reception power for the organizational information oi and uses it as a reference for decisions to switch to other cells and for power regulation.

Landscapes

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

Priority Applications (2)

Applications Claiming Priority (2)

Publications (2)

Family

ID=7825274

Family Applications (1)

Country Status (7)

Families Citing this family (5)

Citations (3)

Family Cites Families (1)

• 1997
  • 1997-04-02 DE DE19713667A patent/DE19713667C1/de not_active Expired - Fee Related
• 1998
  • 1998-03-12 EP EP98923996A patent/EP0972362A2/de not_active Ceased
  • 1998-03-12 CN CN98803920A patent/CN1252192A/zh active Pending
  • 1998-03-12 WO PCT/DE1998/000730 patent/WO1998044662A2/de not_active Application Discontinuation
  • 1998-03-12 AU AU76370/98A patent/AU7637098A/en not_active Abandoned
  • 1998-03-31 ZA ZA982686A patent/ZA982686B/xx unknown
  • 1998-03-31 AR ARP980101464A patent/AR010138A1/es not_active Application Discontinuation

Patent Citations (3)

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