Title:
BIDIRECTIONAL COMMUNICATION SYSTEM AND METHOD FOR DECIDING INCOMING COMMUNICATION NOISE LEVEL
Document Type and Number:
Japanese Patent JP3560465
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To maintain the quality of an incoming signal at a constant level by making a center device receive a reference pattern signal, whose transmission level is controlled, measuring the receiving level of the reference pattern signal, and deciding a noise level in the receiving level in accordance with the propriety of measurement.
SOLUTION: A receiving level of a reference pattern signal that is transmitted from a terminal 20 is measured by a level measuring part 14 of a center device 10. When the receiving level is measurable or unmeasurable, a level change controlling part 16 transmits an instruction signal that lowers or raises the transmission level by prescribed width to the terminal 20. A pattern generating part 26 of the terminal 20 generates the reference pattern signal again, and a level control part 24 lowers or raises the transmission level and transmits it to the device 10 from a transmitting part 23. The part 16 calculates the difference between the last unmeasurable transmission level that is one previous to a measurable notice and the level of a transmission loss as a noise level and sets a receiving level that satisfies a prescribed C/N value.
Inventors:
Masayuki Nishimura
Application Number:
JP6633898A
Publication Date:
September 02, 2004
Filing Date:
March 17, 1998
Export Citation:
Assignee:
富士通株式会社
International Classes:
H04B3/04; H04B3/46; H04B7/005; H04B15/00; H04B17/00; H04L5/16; H04N7/173; H04N21/24; H04N21/437; H04N21/647; (IPC1-7): H04B3/46; H04B3/04; H04B15/00; H04L5/16; H04N7/173
Domestic Patent References:
| JP4119724A | ||||
| JP3188784A | ||||
| JP63151122A |
Attorney, Agent or Firm:
Hayashi Tsunetoku
Kenji Doi
Kenji Doi
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