US5640413A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital mobile radio communication system
Assignee: NEC Corp
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Filing: 1994-01-21
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Granted: 1997-06-17
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Expires: 2014-01-21
Abstract
Abstract A base station and a plurality of mobile stations are coupled by down and up radio communication lines. In base station, a spread spectrum signal is generated on the basis of a base station timing signal generated therein. In the mobile station, the spread spectrum signal transmitted from the base station is despread in spectrum by a mobile station timing signal. The mobile station timing signal is changed in generating timing to be determined by monitoring a despread spectrum signal as to whether an encoded data is observed or not therein.
Inventors
- 👤 Masaki Ichihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:13
CPC Classifications
H; H04; H04W; H04W56/00; H04W56/001; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2662; H04B7/2668
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
144 words
A digital mobile radio communication system, comprising: a base station comprising a CDMA transmitter for transmitting a spread spectrum signal, a TDMA receiver for receiving a TDMA transmitted signal, and a timing generator for generating a base station timing signal; and a plurality of mobile stations each coupled via a down line and a up line to said base station, each of said mobile stations comprising a CDMA receiver for receiving said spread spectrum signal via said down line from said base station, a TDMA transmitter for transmitting a TDMA transmitting signal via said up line to said base station; wherein said CDMA receiver comprises means for generating a mobile station timing signal in accordance with a despread spectrum signal obtained from said spread spectrum signal received in said CDMA receiver; and said TDMA transmitter operates in accordance with said mobile station timing signal.
Claim 2
Dependent Claim
144 words
A digital mobile radio communication system, comprising: a base station comprising a CDMA transmitter for transmitting a spread spectrum signal, a TDMA receiver for receiving a TDMA transmitted signal, and a timing generator for generating a base station timing signal; and a plurality of mobile stations each coupled via a down line and a up line to said base station, each of said mobile stations comprising a CDMA receiver for receiving said spread spectrum signal via said down line from said base station, a TDMA transmitter for transmitting a TDMA transmitting signal via said up line to said base station; wherein said CDMA receiver comprises means for generating a mobile station timing signal in accordance with a despread spectrum signal obtained from said spread spectrum signal received in said CDMA receiver; and said TDMA transmitter operates in accordance with said mobile station timing signal.
Claim 3
Dependent Claim
170 words
A digital mobile radio communication system, according to claim 1, wherein: said CDMA transmitter comprises an encoder for encoding a transmitting data to provide a transmitting code signal, means for generating a spread spectrum code signal, a multiplier for multiplying said transmitting code signal and said spread spectrum code signal to provide said spread spectrum signal, and a RF modulator for modulating a high frequency signal by said spread spectrum signal to provide a base station high frequency transmitting signal; and said CDMA receiver comprises a RF demodulator for demodulating a mobile station received signal obtained by receiving said base station high frequency transmitting signal to provide a demodulated signal, means for generating a despread spectrum code signal, a multiplier for multiplying said demodulated signal and said despread spectrum code signal to provide a despread spectrum signal, and a decoder for decoding said despread spectrum signal to provide a received data, said despread spectrum code signal generating means being controlled in signal generating timing by said base station timing signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-06-16 | 2000-12-16 | 2001-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-16 | 2004-12-16 | 2005-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-16 | 2008-12-16 | 2009-06-17 | $7700.00 | Window Closed / Lapsed |