Title:
MODULATOR USING ZERO CROSS DETECTION, AND METHOD THEREFOR
Document Type and Number:
Japanese Patent JP3193016
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide band spread device and method by which orthogonality between transmission signals in a CDMA communication system is stably maintained.
SOLUTION: This modulator that modulates 1st and 2nd input signals consists of a zero cross detector 241 that detects zero cross numbers between the 1st and 2nd input signals, a 1st delay device 243 that delays the 1st input signal, a 2nd delay device 245 that delays the 2nd input signal by a delay time different from that of the 1st delay device, selectors 247, 249 that select outputs of the 1st and 2nd delay devices as 1st and 2nd channel signals when a zero cross check device detects number of zero crossing and select the 1st and 2nd input signals as the 1st and 2nd channel signals when no zero crossing is detected, and modulators 251, 253 that modulate the 1st and 2nd channel signals by the QPSK method.
Inventors:
Park Jong Hyun
Kim Je Woo
Kim Je Woo
Application Number:
JP5611399A
Publication Date:
July 30, 2001
Filing Date:
March 03, 1999
Export Citation:
Assignee:
Samsung Electronics Co.,Ltd.
International Classes:
H04B1/707; H04J11/00; H04L27/20; (IPC1-7): H04B1/707; H04L27/20
Domestic Patent References:
| JP5114894A | ||||
| JP8172460A | ||||
| JP8335925A | ||||
| JP60180359A | ||||
| JP61128654A | ||||
| JP396037A |
Attorney, Agent or Firm:
Shogo Ohtake