AU751483B2 - A method for assigning spreading codes - Google Patents
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- AU751483B2 AU751483B2 AU90127/98A AU9012798A AU751483B2 AU 751483 B2 AU751483 B2 AU 751483B2 AU 90127/98 A AU90127/98 A AU 90127/98A AU 9012798 A AU9012798 A AU 9012798A AU 751483 B2 AU751483 B2 AU 751483B2
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/16—Code allocation
- H04J13/18—Allocation of orthogonal codes
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
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- 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
- H04B7/2628—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/0007—Code type
- H04J13/0022—PN, e.g. Kronecker
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J13/00—Code division multiplex systems
- H04J13/0007—Code type
- H04J13/004—Orthogonal
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2201/00—Indexing scheme relating to details of transmission systems not covered by a single group of H04B3/00 - H04B13/00
- H04B2201/69—Orthogonal indexing scheme relating to spread spectrum techniques in general
- H04B2201/696—Orthogonal indexing scheme relating to spread spectrum techniques in general relating to Dowlink
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Description
A METHOD FOR ASSIGNING SPREADING CODES TECHNICAL FIELD OF THE INVENTION The present invention relates to methods for assigning spreading codes to DS-CDMA forward-link connections.
BACKGROUND OF THE INVENTION CDMA (Code Division Multiple Access) is a method for multiple access in a radio communication system. The CDMA method uses the spread spectrum technique in which a number of users simultaneously occupy the same frequency band with their radio channels.
In a DS-CDMA (Direct Sequence-CDMA) system which is a particular type of the CDMA techniques, each user is assigned a specific spreading code by which the user is separated from the other users of the system. Another name for a spreading code is spreading sequence or spreading-code sequence.
The transmitted information in the radio signal is coded (spread) by a specific spreading code in the transmitter. At the receiving end the coded information is decoded (despread) by correlating with the same specific spreading *i code again or by filtering the received information in a matched filter.
A spreading code of the same length as the symbol interval is called a short spreading code.
Orthogonal codes are codes that have zero cross correlation for zero time offset. The use of orthogonal codes will reduce the intra-cell interference, i.e.
interference from other forward-link signals in the same cell. Normally the intracell *l WO 99/12284 PCT/SE98/01541 2 interference will not be completely eliminated as time dispersion will partly destroy the orthogonality between signals coded with orthogonal codes.
In general, a set of orthogonal codes does only contain a finite number of codes, where the number of codes is always smaller or the same as the length of the codes.
Consequently, as there are only a finite number of orthogonal spreading codes available, spreading codes which are almost orthogonal or non-orthogonal has to be used to increase the number of simultaneous users or increase the bit-rate of the system.
On a DS-CDMA forward-link (transmission from a base station to a radio unit), orthogonal spreading codes are often used to separate different radio channels.
When a connection through a radio channel uses more than one spreading code, it is said to use so-called multi-code transmission.
For variable bit-rate connections, i.e. a connection where the bit-rate varies during the duration of a call, the number of spreading codes actually used by each connection will vary in time and between the different connections. A high bit-rate uses more spreading codes than a lower bit-rate.
One example of a scheme to assign spreading codes to a connection with a variable bit-rate in a radio communication system is the static allocation.
A static allocation means that each connection is, at call setup, allocated as many spreading codes as is needed to be able to transmit at a requested maximum bit-rate.
WO 99/12284 PCT/SE98/01541 3 This means that a small number of connections with variable bitrate connection might allocate all available spreading codes even if they do not have to use all of them simultaneous.
Another example of a scheme to assign spreading codes to a connection is the dynamic allocation.
A dynamic allocation means that all connections share a common pool of spreading codes that are continuously redistributed by a base station, according to the instantaneous need of each connection.
Each time the bit-rate at a connection is to be increased the base station has to inform the radio unit what new spreading codes to receive. This will require a significant overhead in the communication between the base station and radio unit.
The US patent US 5 533 013 describes a method and a system for assigning complete orthogonal spreading codes and radio channels in a combined CDMA/TDMA or TDMA/CDMA communication system. Said method comprises the step of assigning an orthogonal spreading code selected from a set of complete orthogonal spreading codes.
Said system comprises means for assigning orthogonal spreading codes selected from at least one code set of complete orthogonal spreading codes. If more than one set, the code sets of complete orthogonal spreading codes have been selected so that they are completely orthogonal in relation to each other.
The US patent US 5 452 328 describes a method for assigning disjoint sets of binary spreading-code sequences to different nodes in a multi-node communication network.
Each node in the network is allotted spreading-code sequences which are selected from a family of "almost orthogonal" binary sequences. The patent also describes an apparatus and a method 4 for generating said family of sequences by combining a first and a second multistage shift register.
As will be seen herein, each of the methods disclosed in these patents is of a different construction than the method of the present invention.
The name radio unit includes all portable and non-portable equipment intended for radio communication, like mobile phones, pagers, telex, electronic notebooks and communicators. This equipment can be used in any type of radio communication system, such as cellular networks, satellite or small local networks.
Any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the invention. It should not be taken as an admission that any of the material formed part of the prior art base or the common general knowledge in the relevant art in Australia on or before the priority date of the claims herein.
SUMMARY OF THE INVENTION The present invention meets problems related to how a forward-link connection is assigned specific spreading codes in a DS-ODMA communication system where only a finite number of orthogonal spreading codes are available.
One problem occurs when the system is using static allocation for variable bit-rate connections. The system may run out of spreading codes even if only a small number of spreading codes are actually used simultaneous. Each S° connection has allocated the amount of spreading codes that is needed for the maximum bit-rate irrespective of if the maximum bit-rate is needed for only a short time.
Another problem occurs when the system is using dynamic allocation for variable bit-rate connections. A significant overhead in the communication between the base station and the radio unit is needed to inform the radio unit what new spreading codes to receive each time the bit-rate is increased.
In light of the foregoing, a primary object of the present invention is to provide methods and means to assign spreading codes for radio units in a DS- CDMA communication system with variable bit-rate connections.
Another object of the present invention is to provide a large number of available spreading codes which is not limited by the amount of orthogonal spreading codes available in a DS-CDMA communication system.
A further object of the present invention is to avoid re-allocation of spreading codes during the call in a DS-CDMA communication system.
In one aspect, the present invention provides a method for assigning spreading codes to corresponding forward-link connections in a DS-CDMA communication system having a plurality of radio units including the following steps: a) assigning a first number of spreading codes from a first set of orthogonal spreading codes to a first forward-link connection; b) assigning a first part of complete spreading codes of a second number of spreading codes from said first set of spreading codes to a second forward-link connection; c) assigning a second part of complete spreading codes of said second number of spreading codes from a second set of orthogonal spreading ?codes to said second forward-link connection, where at least one of said spreading codes of said second set are non-orthogonal to at least one of said spreading codes of said first set.
In another aspect, the present invention provides A method for assigning a number of spreading codes to a first corresponding forward-link connection among a plurality of forward-link connections in a DS-CDMA communication system having a plurality of radio units, including the following steps: 0% a) assigning a first group of complete spreading codes to said first S 25 forward-link connection from a selected first set of orthogonal spreading codes; b) assigning a second group of complete spreading codes to said first forward-link connection from a selected second set of orthogonal spreading codes, where at least one of said spreading codes of said second set are nonorthogonal to at least one of said spreading codes of said first set, and where said first and second group of spreading codes includes said number of spreading codes needed for said forward-link connection.
In a further aspect, the present invention provides a method for assigning a total number of spreading codes to corresponding forward-link connections with 6 variable bit-rate in a DS-CDMA communication system having a plurality of radio units including the following steps: a) assigning a first group of complete spreading codes to a first forward-link connection from a first set of orthogonal spreading codes; b) assigning a first group of complete spreading codes to a second forward-link connection from said first set of orthogonal spreading codes; c) assigning a second group of complete spreading codes to said first forward-link connection from a second set of orthogonal spreading codes, where at least one of said spreading codes of said second set are non-orthogonal to at least one of said spreading codes of said first set, and where said first and second group of spreading codes to said first forward-link connection includes the total number of spreading codes needed for said first forward-link connection; d) assigning a second group of complete spreading codes to said second forward-link connection from said second set of orthogonal spreading codes, where said first and second group of spreading codes to said second forward-link connection includes the total number of spreading codes needed for said second forward-link connection.
One advantage of some embodiments of the present invention is that the number of simultaneous allocated spreading codes is not hard limited by the size of a code set.
Another advantage of various embodiments of the invention is that each connection is allocated a number of spreading codes at call set-up, and no further spreading code re-allocation is needed.
"Comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
WO 99/12284 PCT/SE98/01541 7 BRIEF DESCRIPTION OF THE DRAWINGS These above mentioned objects and other features of the present invention will become more readily apparent upon reference to the following description when taken in conjunction with the accompanying drawings.
Figure 1 is an illustration of a base station and four radio units in a DS-CDMA communication system.
Figure 2 is an illustration of an example of a set of code sets in accordance with the present invention.
Figure 3 is a first part of a flow chart illustrating a first embodiment of a method in accordance with the present invention.
Figure 4 is a second part of the flow chart in figure 3.
Figure 5 is an illustration of a set of code sets with assigned spreading codes in accordance with the first embodiment in figure 3 and 4.
Figure 6a is a first part of a flow chart illustrating a second embodiment of a method in accordance with the present invention.
Figure 6b is a second part of the flow chart in figure 6a.
Figure 7 is an illustration of four groups of spreading codes.
Figure 8 is an illustration of a set of code sets with assigned spreading codes in accordance with the second embodiment in figure 6a-b.
WO 99/12284 PCT/SE98/01541 DETAILED DESCRIPTION OF EMBODIMENTS The present invention relates to methods for assigning spreading codes to forward-link connections in DS-CDMA communication systems. The forward-link connections are radio connections where the bit-rate can be varied (variable bit-rate) during the duration of a call.
The spreading codes can be assigned at call set-up and e.g. at handover and during set-up of additional services.
Figure 1 shows a base station B and four radio units Ul-U4 in a DS-CDMA communication system. Each radio unit Ul-U4 has a forward-link connection Cl-C4, with a variable bit-rate, between the base station B and the respective unit Ul-U4.
When a first forward-link connection C1 between the base station B and the radio unit U1 is to be set up a specified number of spreading codes are assigned to the first forward-link connection C1 by the base station B or by some other part of the communication system. The spreading codes assigned to this forward-link connection C1 can not be assigned to new forwardlink connections C2-C4 within the same cell as long as the first forward-link connection Cl is up.
The number of spreading codes which are assigned to each of the connections is determined by the desired bit-rate according to the following: A connection with a high bit-rate needs more spreading codes than a connection with a low bit-rate.
A connection with multi-code transmission uses several codes in parallel to increase the bit-rate.
WO 99/12284 PCT/SE98/01541 9 Figure 2 shows an example of a set 20 of code sets Si-Sn according to the present invention. A first code set S1 comprises a number of orthogonal spreading codes mi.
A second code set S2 also comprises a number of orthogonal spreading codes m 2 These spreading codes are orthogonal in relation to each other but non-orthogonal in relation to the spreading codes in the first code set S1.
A third code set S3 also comprises a number of orthogonal spreading codes m 3 These spreading codes are orthogonal in relation to each other but non-orthogonal in relation to the spreading codes in the first and second code set S1 and S2.
The number of code sets n with spreading codes can be more than three.
Figure 3 and 4 show a flow chart of a first embodiment of a method according to the present invention where a number of spreading codes corresponding to a requested bit-rate are assigned to a variable bit-rate forward-link connection C1.
In a step 31a the number of spreading codes needed to transmit at the requested bit-rate between a base station B and a radio unit U1 on the forward-link connection C1 is determined.
In a step 31b the number of available (not assigned) spreading codes in all available code sets is determined. If there are less spreading codes available than the spreading codes needed the method ends, otherwise it continues with a step 32.
In step 32 the number of available (not assigned) spreading codes in a selected first set S1 of orthogonal spreading codes is determined. If there are no available spreading codes in the first set S1 of spreading codes the method continues with a step If there are available spreading codes in the first set S1 of spreading codes the method continues with a step 33.
WO 99/12284 PCT/SE98/01541 In step 33 a number of spreading codes, not exceeding the number of spreading codes needed on the forward-link connection C1, are assigned from the first set S1 of spreading codes to the forward-link connection C1.
In a step 34 the number of spreading codes needed is compared with the number of spreading codes assigned from the first set S1 of spreading codes. The method ends if the number of spreading codes needed are equal to the number of spreading codes assigned from the first set S1 of spreading codes, otherwise it continues with a step In step 35 the number of available spreading codes in a selected second set S2 of orthogonal spreading codes is determined. If there are no available spreading codes in the second set S2 of spreading codes the method continues with a step 38. If there are available spreading codes in the second set S2 of spreading codes the method continues with a step 36.
In step 36 a number of spreading codes, not exceeding the number of spreading codes needed on the forward-link connection Cl, are assigned to the forward-link connection C1.
In a step 37 the number of spreading codes needed is compared with the number of spreading codes assigned from the first and second set of spreading codes SI, S2 respectively. The method ends if the number of spreading codes needed are equal to the number of spreading codes assigned from the first and second set of spreading codes SI, S2 respectively, otherwise it continues with step 38.
In step 38, shown in figure 4, the number of code sets is determined. The method continues with a step 39 if the number of code sets is three, otherwise it ends.
WO 99/12284 PCT/SE98/01541 11 In step 39 the number of available spreading codes in a selected third set S3 of orthogonal spreading codes is determined. If there are no available spreading codes in the third set S3 of spreading codes the method continues with a step 42. If there are available spreading codes in the third set S3 of spreading codes the method continues with a step In step 40 a number of spreading codes, not exceeding the number of spreading codes needed on the forward-link connection C1, are assigned from the third set S3 of spreading codes.
In a step 41 the number of spreading codes needed is compared with the number of spreading codes assigned from the first, second and third set of spreading codes S1, S2, S3 respectively.
The method ends if the number of spreading codes needed are equal to the number of spreading codes assigned from the first, second and third set of spreading codes SI, S2, S3 respectively, otherwise it continues with step 42.
In step 42, the number of code sets is determined. If the number of code sets is three the method ends, otherwise it continues with more steps similar to the previous steps 39-42 as long as there are more spreading codes to be assigned and more sets Si- Sn of codes available.
The method according to figure 3 and 4 is repeated each time a new forward-link connection is to be set-up.
Figure 5 shows an illustration of a set 50 of code sets Si-Sn comprising spreading codes according to the first embodiment.
The first forward-link connection C1 between the base station B and the radio unit U1, see figure 1, has been assigned a first number of spreading codes x from the first set S1 of spreading codes. A second forward-link connection C2 has been assigned a second number of spreading codes y. A first part y-kl of the WO 99/12284 PCT/SE98/01541 12 second number of spreading codes y are taken from the first set S1 of spreading codes and is assigned to the second forward-link connection C2. The first part y-kl of the second number of spreading codes y comprises at least one complete spreading code. A second part k, of the second number of spreading codes y is taken from the second set S2 of spreading codes and is assigned to the second forward-link connection C2. The second part k, of the second number of spreading codes y comprises at least one complete spreading code. The number of non-assigned spreading codes in the first set S1 of spreading codes were less than y so more spreading codes where assigned from the second set S2 of spreading codes.
A third forward-link connection C3 has been assigned a third number of spreading codes z from the second set S2 of spreading codes.
A fourth forward-link connection C4 has been assigned a fourth number of spreading codes w. A first part w-k 2 of the fourth number of spreading codes w is taken from the second set S2 of spreading codes and is assigned to the fourth forward-link connection C4. The first part w-k 2 of the fourth number of spreading codes w comprises at least one complete spreading code. A second part k 2 of the fourth number of spreading codes w is taken from the third set S3 of spreading codes and is assigned to the fourth forward-link connection C4. The second part k 2 of the fourth number of spreading codes w comprises at least one complete spreading code.
Figures 6a-b show a flow chart of a second embodiment of a method according to the present invention where a number of spreading codes corresponding to a requested bit-rate are assigned to a forward-link connection C1 with variable bit-rate.
In a step 61a a total number of spreading codes needed to transmit at the requested bit-rate between the base station B WO 99/12284 PCT/SE98/01541 13 and a radio unit U1 on the forward-link connection C1 is determined.
In a step 61b the number of available (not assigned) spreading codes in all available code sets is determined. If there are less spreading codes available than the total number of spreading codes needed the method ends, otherwise it continues with a step 62.
In step 62 the total number of spreading codes needed is divided in a first and a second group x 2 respectively. The number of spreading codes needed in the first group x, corresponds to the number of spreading codes which will be most frequently used on the forward-link connection Cl. The number of spreading codes needed in the second group x 2 corresponds to the number of spreading codes which will be less frequently used on the forward-link connection C1. Together the first and second group x 1 x 2 respectively will include the total number of spreading codes needed for the forward-link connection C1.
In a step 63 the number of available (not assigned) spreading codes in a selected first set S1 of orthogonal spreading codes is determined. If there are no available spreading codes in the first set S1 of spreading codes the method continues with a step see page 14. If there are available spreading codes in the first set S1 of spreading codes the method continues with a step 64.
In step 64 a number of spreading codes, not exceeding the number of spreading codes needed to the first group xj, are assigned to the first group of spreading codes x, from the first set S1 of spreading codes.
In a step 65 the number of spreading codes needed in the first group x, is compared with the number of spreading codes assigned WO 99/12284 PCT/SE98/01541 14 from the first set S1 of spreading codes. If the number of spreading codes needed in the first group x, is equal to the number of spreading codes assigned from the first set Si of spreading codes the method continues with a step 66 to assign spreading codes to the second group x 2 otherwise it continues with step 70 to assign more spreading codes to the first group xl.
In step 66, shown in figure 6b, the number of available (not assigned) spreading codes in a selected second set S2 of orthogonal spreading codes is determined. If there are no available spreading codes in the second set S2 of spreading codes the method continues with a step 69. If there are available spreading codes in the second set 52 of spreading codes the method continues with a step 67.
In step 67 a number of spreading codes, not exceeding the number of spreading codes needed to the second group x 2 are assigned to the second group x 2 from the second set S2 of spreading codes.
In a step 68 the number of spreading codes needed in the second group x 2 is compared with the number of spreading codes assigned from the second set S2 of spreading codes. The method ends if the number of spreading codes needed in the second group x 2 is equal to the number of spreading codes assigned from the second set S2 of spreading codes, otherwise it continues with step 69 to assign more spreading codes to the second group x 2 In step 69, the number of code sets is determined. The method continues with steps similar to the previous steps 63-69 if the number of code sets is more than two, otherwise it ends.
WO 99/12284 PCT/SE98/01541 In step 70 the number of available spreading codes in the selected second set S2 of orthogonal spreading codes is determined.
If there are no available spreading codes in the second set S2 of spreading codes the method continues with a step similar to step 69 to search for more code sets. If there are available spreading codes in the second set S2 of spreading codes the method continues with a step where spreading codes is assigned to the first group x, from the second code set S2.
The spreading codes to the second group x 2 is then assigned from a third set S3 of spreading codes.
The method according to figures 6a-b continue with steps similar to the previous steps 63-70 as long as there are more spreading codes to be assigned and more sets of codes Si-Sn available.
The method is repeated each time a new forward-link connection with variable bit-rate is to be set-up.
Figure 7 shows an example of four groups of spreading codes G1, G2, G3, G4 respectively assigned to four different variable bitrate forward-link connections Cl-C4. Each group GI, G2, G3, G4 respectively comprises the total number of spreading codes needed in each forward-link connection Cl-C4. The total number of spreading codes needed in each forward-link connection Cl-C4 is divided in the first and second group of spreading codes xj, yl, zl, wl X 2 Y2, z 2 w 2 respectively, where each group x 1 Yi, z 1 w 1 x 2
Y
2 z 2 w 2 respectively comprises complete spreading codes.
Figure 8 shows an illustration of a set 80 of code sets Si-Sn according to the second embodiment of the method in figure 6.
The first forward-link connection C1 with variable bit-rate between the base station B and the radio unit U1, see figure 1, has been assigned spreading codes from the first S1 and second WO 99/12284 PCT/SE98/01541 16 S2 code set. The first group x, of spreading codes has been assigned from the first code set S1 and the second group x 2 of spreading codes has been assigned from the second code set S2.
The second forward-link connection C2 with variable bit-rate between the base station B and the radio unit U2, see figure i, has been assigned spreading codes from the first S1 and second S2 code set. The first group yj of spreading codes has been assigned from the first code set Si and the second group Y2 of spreading codes has been assigned from the second code set S2.
The third forward-link connection C3 with variable bit-rate between the base station B and the radio unit U3, see figure 1, has been assigned spreading codes from the first S1 and second S2 code set. The first group z, of spreading codes has been assigned from the first code set S1 and the second group z 2 of spreading codes has been assigned from the second code set S2.
The fourth forward-link connection C4 with variable bit-rate between the base station B and the radio unit U4, see figure i, has been assigned spreading codes from the first S1 and third S3 code set. The first group w, of spreading codes has been assigned from the first code set S1 and the second group w 2 of spreading codes has been assigned from the third code set S3.
There were no non-assigned spreading codes in the second code set S2 left so more spreading codes where assigned from the third code set S3.
The signals which have been coded by short spreading codes in the methods according to the present invention can be scrambled.
Signals in a forward-link connection which have been coded by short spreading codes is scrambled by a common (long) Pseudo- Noise code (PN-code). The scrambling randomise the interference between the cells. The scrambling will not affect the orthogonality between the signals in one cell as all signals WO 99/12284 PCT/SE98/01541 uses the same PN-code. The neighbouring cells uses different PNcodes.
Claims (8)
1. A method for assigning spreading codes to corresponding forward-link connections in a DS-CDMA communication system having a plurality of radio units including the following steps: a) assigning a first number of spreading codes from a first set of orthogonal spreading codes to a first forward-link connection; b) assigning a first part of complete spreading codes of a second number of spreading codes from said first set of spreading codes to a second forward-link connection; c) assigning a second part of complete spreading codes of said second number of spreading codes from a second set of orthogonal spreading codes to said second forward-link connection, where at least one of said spreading codes of said second set are non-orthogonal to at least one of said spreading codes of said first set.
2. A method for assigning a number of spreading codes to a first V.00 corresponding forward-link connection among a plurality of forward-link o *0connections in a DS-CDMA communication system having a plurality of radio units, including the following steps: oooo a) assigning a first group of complete spreading codes to said first forward-link connection from a selected first set of orthogonal spreading codes; b) assigning a second group of complete spreading codes to said first forward-link connection from a selected second set of orthogonal spreading codes, where at least one of said spreading codes of said second set are non- orthogonal to at least one of said spreading codes of said first set, and where said •0 first and second group of spreading codes includes said number of spreading codes needed for said forward-link connection.
3. A method as claimed in any one of the preceding claims, wherein said assigning according to step a) b) includes assigning the spreading codes to said first forward-link connection at call set-up. 19
4. A method as claimed in any one of the preceding claims, wherein said number of spreading codes needed to correspond to said first forward-link connection is determined by a requested maximum bit-rate.
A method as claimed in any one of the preceding claims, wherein said forward-link connection is a variable bit-rate forward-link connection.
6. A method a claimed in any one of the preceding claims, wherein said DS- CDMA communication system provides multi-code transmission.
7. A method for assigning a total number of spreading codes to corresponding forward-link connections with variable bit-rate in a DS-CDMA communication system having a plurality of radio units including the following steps: a) assigning a first group of complete spreading codes to a first forward-link connection from a first set of orthogonal spreading codes; b) assigning a first group of complete spreading codes to a second forward-link connection from said first set of orthogonal spreading codes; c) assigning a second group of complete spreading codes to said first forward-link connection from a second set of orthogonal spreading codes, where *.at least one of said spreading codes of said second set are non-orthogonal to at least one of said spreading codes of said first set, and where said first and second group of spreading codes to said first forward-link connection includes the total number of spreading codes needed for said first forward-link connection; Sd) assigning a second group of complete spreading codes to said second forward-link connection from said second set of orthogonal spreading codes, where said first and second group of spreading codes to said second forward-link connection includes the total number of spreading codes needed for said second forward-link connection.
8. A method of assigning spreading codes according to any one of claims 1, 2 or 7 substantially as herein before described with reference to the accompanying drawings. DATED this 15th day of April 2002 TELEFONAKTIEBOLAGET LM ERICSSON (publ) WATERMARK PATENT TRADE MARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA RCS/NWM/SH **e
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE9703161 | 1997-09-02 | ||
| SE9703161A SE9703161L (en) | 1997-09-02 | 1997-09-02 | Procedure for telecommunications |
| PCT/SE1998/001541 WO1999012284A1 (en) | 1997-09-02 | 1998-08-28 | A method for assigning spreading codes |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU9012798A AU9012798A (en) | 1999-03-22 |
| AU751483B2 true AU751483B2 (en) | 2002-08-15 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU90127/98A Ceased AU751483B2 (en) | 1997-09-02 | 1998-08-28 | A method for assigning spreading codes |
Country Status (13)
| Country | Link |
|---|---|
| EP (1) | EP1010266A1 (en) |
| JP (1) | JP2001515302A (en) |
| KR (1) | KR20010023600A (en) |
| CN (1) | CN1118963C (en) |
| AR (1) | AR017048A1 (en) |
| AU (1) | AU751483B2 (en) |
| BR (1) | BR9811428A (en) |
| CA (1) | CA2299297A1 (en) |
| FI (1) | FI20000460A (en) |
| SE (1) | SE9703161L (en) |
| TW (1) | TW393843B (en) |
| WO (1) | WO1999012284A1 (en) |
| ZA (1) | ZA986672B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI982203A (en) * | 1998-10-09 | 2000-04-10 | Nokia Networks Oy | Method and generator for generating an orthogonal spreading code in a CDMA radio system |
| EP1112632B1 (en) | 1999-07-07 | 2005-04-13 | Samsung Electronics Co., Ltd. | Apparatus and method for generating scrambling code in umts mobile communication system |
| KR100396653B1 (en) * | 1999-12-30 | 2003-09-02 | 엘지전자 주식회사 | Transmission method for multiple chip rate in mobile communications system |
| JP3565102B2 (en) | 1999-08-13 | 2004-09-15 | 日本電気株式会社 | Downlink spreading code allocation method and base station |
| KR100429545B1 (en) * | 1999-08-17 | 2004-04-28 | 삼성전자주식회사 | Method for communicating scrambling code id in mobile communication system |
| FR2820933B1 (en) * | 2001-02-09 | 2003-05-30 | Sagem | TEST METHOD AND TOOL FOR CELLULAR MULTIPLEXED CELLULAR RADIO TELEPHONY NETWORK |
| KR100449546B1 (en) * | 2001-10-08 | 2004-09-21 | 주식회사 카서 | Code select cdma modulation and demodulation method and device thereof |
| KR100444845B1 (en) * | 2002-04-12 | 2004-08-21 | 주식회사 카서 | Coding method and apparatus for constant amplitude transmission in code select cdma communication system and device thereof |
| FR2844134B1 (en) * | 2002-09-04 | 2006-01-13 | Nortel Networks Ltd | METHOD OF ALLOCATING RESOURCES IN A RADIO COMMUNICATION SYSTEM WITH SPATIAL DIVISION AND EQUIPMENT FOR IMPLEMENTING THE METHOD. |
| WO2006004550A2 (en) | 2004-07-06 | 2006-01-12 | Telefonaktiebolaget Lm Ericsson (Publ) | Non-contiguous variable length orthogonal codes |
| KR100662506B1 (en) * | 2004-08-04 | 2006-12-28 | 한국전자통신연구원 | Apparatus and its method for deciding user code according to number of connecting user and, apparatus and its method for generating user code using the same in quasi-synchronous cdma system |
| CN1921362B (en) * | 2005-08-23 | 2011-09-21 | 中兴通讯股份有限公司 | Orthogonal variable spread-spectrum code distribution method in code division multiple access communication system |
| CN101388685B (en) * | 2007-09-12 | 2014-02-19 | 中兴通讯股份有限公司 | Code resource management method |
| GB2495709B (en) * | 2011-10-17 | 2014-12-10 | Aetheric Engineering Ltd | Communication system and method of operating the same |
| EP2739104A1 (en) * | 2012-11-28 | 2014-06-04 | Alcatel-Lucent | A cellular telecommunications base station and a method of allocating a spreading code |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO1997015985A1 (en) * | 1995-10-26 | 1997-05-01 | Nokia Mobile Phones Limited | Data transmission method, transmitter, and receiver |
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| US5210770A (en) * | 1991-09-27 | 1993-05-11 | Lockheed Missiles & Space Company, Inc. | Multiple-signal spread-spectrum transceiver |
| MY112371A (en) * | 1993-07-20 | 2001-05-31 | Qualcomm Inc | System and method for orthogonal spread spectrum sequence generation in variable data rate systems |
| US5515396A (en) * | 1994-02-25 | 1996-05-07 | Motorola, Inc. | Method and apparatus for selecting a spreading code in a spectrum spread communication system |
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1997
- 1997-09-02 SE SE9703161A patent/SE9703161L/en not_active Application Discontinuation
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1998
- 1998-07-16 TW TW087111586A patent/TW393843B/en not_active IP Right Cessation
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- 1998-08-28 AU AU90127/98A patent/AU751483B2/en not_active Ceased
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997015985A1 (en) * | 1995-10-26 | 1997-05-01 | Nokia Mobile Phones Limited | Data transmission method, transmitter, and receiver |
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| SE9703161L (en) | 1999-03-03 |
| AR017048A1 (en) | 2001-08-22 |
| CA2299297A1 (en) | 1999-03-11 |
| BR9811428A (en) | 2000-08-22 |
| CN1118963C (en) | 2003-08-20 |
| FI20000460A (en) | 2000-02-29 |
| JP2001515302A (en) | 2001-09-18 |
| AU9012798A (en) | 1999-03-22 |
| KR20010023600A (en) | 2001-03-26 |
| TW393843B (en) | 2000-06-11 |
| ZA986672B (en) | 1999-04-01 |
| CN1269927A (en) | 2000-10-11 |
| WO1999012284A1 (en) | 1999-03-11 |
| EP1010266A1 (en) | 2000-06-21 |
| SE9703161D0 (en) | 1997-09-02 |
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