Title:
SCRAMBLE CODE REVISION METHOD DURING COMMUNICATION
Document Type and Number:
Japanese Patent JP3550165
Kind Code:
B2
Abstract:
PURPOSE: To revise a scramble code during communication regardless of a line operating state.
CONSTITUTION: A base station generates a random number during communication, sends the random number and an original code designation signal 501 to a mobile station and generates a scramble code based on the random number and the original code. The mobile station generates the scramble code from the received random number and original code and sends a generation end signal 502 to the base station. The base station receiving the signal 502 sends a synchronization establish signal 503 to the mobile station in place of a communication signal. When the communication is interrupted to cause out of synchronism and the state is detected, a synchronization establish mode is set to the mobile station and re-synchronization processing is executed by a synchronization establish signal 504 sent succeedingly and when the resynchronization is established, the scramble code generated before is used to make scramble of communication between the mobile station and the base station.
Inventors:
Akihiro Maehara
Seizo Onoe
Keiichi Terao
Yoshiaki Nakajima
Seizo Onoe
Keiichi Terao
Yoshiaki Nakajima
Application Number:
JP13476693A
Publication Date:
August 04, 2004
Filing Date:
June 04, 1993
Export Citation:
Assignee:
NTT DoCoMo, Inc.
International Classes:
H04W12/00; H04B7/26; H04L9/06; H04L9/12; H04L9/14; H04L9/16; (IPC1-7): H04L9/12; H04L9/16; H04Q7/38
Domestic Patent References:
| JP4167631A | ||||
| JP6237248A | ||||
| JP4369136A | ||||
| JP4109721A | ||||
| JP63167588A | ||||
| JP62122352A | ||||
| JP61171245A | ||||
| JP60174542A | ||||
| JP55027754A |
Attorney, Agent or Firm:
Taku Kusano
Minoru Inagaki
Yoshinobu Yokota
Minoru Inagaki
Yoshinobu Yokota