Line rate control system in code division multiple connection

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a line speed control system in code division multiple access (CDMA), and more particularly to a line speed control system that allocates line speeds in a situation where constant rate calls and packet calls are mixed.

【0002】

[Conventional technology]

There are two types of data transmission, fixed rate call and packet call. While fixed rate call requires real-time property, packet call allows some delay. Generally, in a situation where fixed-rate calls and packet calls are mixed, both types of connection requests are treated equally, and the connection request is rejected (busy) when the line is full, or when the line congestion level exceeds a certain threshold value. Reject the packet call connection request. A similar line speed allocation system can be applied to CDMA systems. This type of line speed allocation system is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-107769 (Load control method and device of a CDMA cellular system having a circuit-switched terminal device and a packet-switched terminal device). In the load control method and device of the CDMA cellular system disclosed in this publication, the total capacity required to service the first type of terminal is measured at periodic intervals, and the measurement is performed from the current maximum capacity. The amount is deducted, and if there is any remaining capacity, all or part of it is allocated to one or more second-type terminal devices.

【0003】

[Problems to be Solved by the Invention]

However, in the conventional line speed allocation system, the line speed of the packet call remains the same even when the line is busy. Since data flows only intermittently in packet transmission, in a situation where the line is busy, it is better to reduce the line speed of the packet call and accept the fixed rate call with the free line capacity so that the line can be used more effectively. Packet calls with reduced line speeds have shorter line free time. When packet data is continuous, data may accumulate and transmission waiting time may occur, but this is not a problem due to the nature of packet data.

【0004】

Therefore, an object of the present invention is to provide a line speed control system capable of lowering the line speed of a packet call and allocating the vacant line capacity to a new fixed rate call in a situation where the line is congested. ..

【0005】

[Means for solving problems]

The present invention for solving the above problems is a line speed control system in code division multiple access (CDMA) transmission for transmitting a constant rate call and a packet call in code division multiple access (CDMA), and has a constant rate. It has a resetting means for resetting the line speed of the packet call in response to the call connection request, and allocates the remaining communication capacity to the fixed rate call.

【0006】

That is, in the line speed allocation system of the present invention, the packet call speed resetting means is provided, and the packet call speed resetting means can, for example, halve the transmission speed of the packet call in a situation where the line is busy. Is halved. Then, the free line capacity is allocated to a new fixed rate call. For example, halving the transmission speed can be achieved by doubling the length of the spread code in a CDMA system.

【0007】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

【0008】

FIG. 1 is a block diagram of the line speed control system of the present invention. As shown in FIG. 1, the line management unit 81 receives a connection request and a termination notification from the outside. Connection requests include fixed rate calls and packet calls. When the end notification comes, the line management unit 81 instructs the line opening unit 83 to open the line. When a connection request comes and the line is not busy, the line setting unit 82 is instructed to set the requested line. When a fixed rate call connection request comes in when the line is busy, the packet call speed resetting unit 84 is first activated to halve the packet call transmission speed, for example, and as a result, a new fixed rate call is connected. If possible, instruct the line setting unit 82 to set the requested line, and reject the connection if a new fixed-rate call cannot be connected. If a packet call connection request comes in while the line is busy, the request is rejected.

【0009】

FIG. 2 is a flowchart for explaining the operation of the line speed control system of the present invention. As shown in Fig. 2, when there is a connection request, it is first determined whether the request is a fixed rate call or a packet call (step 11).

【0010】

In the case of a packet call, the line speed is allocated within the allottable range and the process ends (step 13). On the other hand, in the case of a fixed rate call, the requested rate is compared with the margin of the line to determine whether or not the allocation is possible at present (step 12). Then, if it can be assigned, the line speed is assigned and the process ends (step 18). On the other hand, if the line has insufficient margin, it is determined whether there is a packet call that can halve the line speed, for example (step 14), and if there is such a packet call, the line speed is halved (step 14). 15) After that, it is determined again whether the line speed can be assigned to the fixed rate call (step 16).

【0011】

If the line speed can be assigned, the line speed is assigned (step 18), and if the line speed cannot be assigned, the connection is rejected (step 17).

【0012】

To reduce the transmission rate to 1/A, the spread code should be A times as long in the CDMA system. When using the hierarchical diffusion code described in IEICE Transactions on Communications, Vol..E-81-B, No.4 (April 1998), pp.777-784 , The diffusion code one step lower in Fig. 3 of the relevant document may be used. For example, if the current spreading code is "1001", by using "10011001" or "10010110" as the new spreading code, the transmission rate can be halved while maintaining orthogonality with other data.

【0013】

[Effect of the invention]

According to the present invention described above, the connection probability of a fixed rate call is determined based on the basic configuration of reducing the line speed of a packet call and allocating the vacant line capacity to a new fixed rate call in a situation where the line is busy. An enhanced line speed control system can be provided.

[Simple explanation of drawings]

[Figure 1]

Block diagram of the line speed control system of the present invention [Figure 2]

Flow chart for explaining the operation of the line speed control system of the present invention [Explanation of symbols]

81 Line Management Department 82 Line setting section 83 Line opening 84 Packet call rate resetting unit