发明名称 |
BAND NARROWING SYSTEM FOR SPREAD SPECTRUM RADIO COMMUNICATION |
摘要 |
PURPOSE:To narrow a occupied frequency band width when the frequency hopping system is employed for the spread spectrum communication by dividing a series of transmission information string into plural lines so as to apply spread spectrum modulation through the use of a multiple access technology. CONSTITUTION:A serial/parallel conversion section 5 of a transmitter 1 distributes information into 3 sets of information strings having a transmission speed of 5kbps and spread spectrum modulation is applied in the frequency hopping system to obtain a spread processing gain of a 27dB by a modulation section. Since the multiple access technology is employed to superimpose the split information string onto the same frequency band in such a way, the occupied frequency band width on the transmission line is 2.5MHz, then improved. Since the multiplex by the multiple access is applied in such a way, the band narrowing processing is attained in comparison with the case of applying spread modulation to each information string as it is and sending the result. |
申请公布号 |
JPH02121423(A) |
申请公布日期 |
1990.05.09 |
申请号 |
JP19880272978 |
申请日期 |
1988.10.31 |
申请人 |
HITACHI LTD;HITACHI ADVANCED SYST:KK |
发明人 |
MORI KATSUHISA;EMORI HAJIME |
分类号 |
H04J13/00;H04B1/66;H04B1/713;H04B14/00 |
主分类号 |
H04J13/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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