摘要 |
To provide a diffusion code generator capable of rendering interception and eavesdropping of communication difficult without influencing communication quality and transmission data. The spreading code generator generates orthogonal code list SP of a diffused information data rate cycle. Scrambling code generators generate M length code Sci, SCq of relatively long cyclicity respectively. Diffusion codes for in-phase components and orthogonal components are computed by ExOR circuits respectively, and diffusion code for in-phase components Ci and diffusion code for orthogonal components Cq are generated. A timer changes orthogonal code list SP currently set in a TTI cycle to another different type. In this case, switching by the timer is possible either only in a TTI cycle or in a cycle of T 2 =N*T 1 (N: integer) taking opportunity of TTI or layer 1 synchronous interval unit T 3.
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