Orthogonal code synchronization system and method for spread spectrum CDMA communications
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
H04B-072/16
H04B-015/00
출원번호
US-0807228
(1997-02-28)
발명자
/ 주소
Lavean Gil
출원인 / 주소
Interdigital Technology Corporation
대리인 / 주소
Volpe and Koenig, P.C.
인용정보
피인용 횟수 :
46인용 특허 :
10
초록▼
A cellular radio system in which a base station receiver can receive, on the reverse link, data from a mobile terminal in one of four control modes. In the first mode, the mobile terminal sends an independent user pilot, not synchronized with the base station, on the reverse link and the user data c
A cellular radio system in which a base station receiver can receive, on the reverse link, data from a mobile terminal in one of four control modes. In the first mode, the mobile terminal sends an independent user pilot, not synchronized with the base station, on the reverse link and the user data channel is synchronized to this independent user pilot. In the second mode, the mobile terminal slaves its user pilot to the pilot it receives from the base station and the user data channel is synchronized with this slaved user pilot. This second mode allows the user terminal to receive round trip delay information for purposes of geolocation and rapid reacquisition. In the third mode, the mobile terminal slaves its user pilot to the incoming base station pilot, as in the case of mode two, but the user data channel operates in the orthogonal mode using the ranging information received from the base station. The phase relationship between the user pilot channel and the user data channel is calibrated. The user pilot carrier is also the carrier for the user data channel and can be used as the carrier reference for detecting the user data channel. In the fourth mode, the slaved pilot implementation of mode three is used for acquisition but, after acquisition, the user pilot code is phase shifted to be synchronous with the user data channel, thus also making it an orthogonal channel. In this mode, the pilots no longer contribute interference to the user data channels, within the cell, and can be transmitted at higher power levels.
대표청구항▼
[ I claim:] [1.] In a spread spectrum CDMA digital cellular radio system for communicating between a base station and a mobile terminal over a duplex radio channel, a mobile terminal comprising:a remote user data source for generating a user data signal;a first orthogonal code set generator for gene
[ I claim:] [1.] In a spread spectrum CDMA digital cellular radio system for communicating between a base station and a mobile terminal over a duplex radio channel, a mobile terminal comprising:a remote user data source for generating a user data signal;a first orthogonal code set generator for generating a first orthogonal code and a first remote pilot code;a first modulo-two adder, coupled to said remote user data source and to said first orthogonal code set generator, for spread spectrum processing the user data signal with the first orthogonal code to generate a spread signal;a first noise-like code generator for generating a first pseudo-noise code;a second modulo-two adder, coupled to an output of said first modulo-two adder and to said first noise-like code generator, for processing the spread signal with the first pseudo-noise code to generate a spread spectrum user data signal;a remote pilot data source for generating a pilot data signal;a third modulo-two adder, coupled to said first orthogonal code set generator and to said remote pilot data source, for spread spectrum processing the pilot data signal with the first remote pilot code to generate a spread pilot signal;a fourth modulo-two adder, coupled to an output of said third modulo-two adder and to said first noise-like code generator, for processing the spread pilot signal with the first pseudo-noise code to generate a remote spread spectrum pilot data signal;a signal combiner, coupled to said fourth modulo-two adder and to said second modulo-two adder, for combining the remote spread spectrum pilot data signal and the spread spectrum user data signal as a combined spread spectrum data signal;a modulator, coupled to said signal combiner, for modulating the combined spread spectrum data signal onto a carrier as a combined spread spectrum modulated data signal;antenna means for transmitting the combined spread-spectrum modulated data signal on a reverse channel and for receiving a composite spread-spectrum modulated carrier signal transmitted from the base station on a forward channel, the composite spread-spectrum modulated carrier signal on the forward channel having a common-shared-spread-spectrum-pilot signal and a specific spread spectrum user information channel for the mobile terminal;a code phase adjuster, coupled to said first orthogonal code set generator and to said first noise-like code generator, for adjusting, responsive to a processor input and to the common-shared-spread-spectrum-pilot signal, a phase of the first orthogonal code to adjust a time of arrival of the spread spectrum user data signal at the base station to be orthogonal with other arriving spread spectrum user data signals, the phase of the first remote pilot code slaved to the common-shared-spread-spectrum-pilot signal to enable the base station to determine a range between the base station and the mobile terminal using round trip delay; anda processor, coupled to said code phase adjuster, for generating the processor input and for storing the range between the base station and the mobile terminal.
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이 특허에 인용된 특허 (10)
Yeung Joemmane Chi Cheung (Wellingborough GBX) Cooper Ian L. (Basingstoke GBX), Apparatus and method of synchronizing a transmitter in a subscriber terminal of a wireless telecommunications system.
Lomp Gary ; Kowalski John ; Ozluturk Fatih ; Silverberg Avi ; Regis Robert ; Luddy Michael ; Marra Alexander ; Jacques Alexander, Code division multiple access (CDMA) communication system.
Lee Edward K. B. (Sunrise FL) Cadd Jimmy (Coral Springs FL) Fulghum Tracy L. (Sunrise FL) Babayi Robert S. (Sunrise FL), System and method for bit timing synchronization in an adaptive direct sequence CDMA communication system.
Gilhousen Klein S. (San Diego CA) Jacobs Irwin M. (La Jolla CA) Padovani Roberto (San Diego CA) Weaver ; Jr. Lindsay A. (San Diego CA) Wheatley ; III Charles E. (Del Mar CA) Viterbi Andrew J. (La Jol, System and method for generating signal waveforms in a CDMA cellular telephone system.
Chang, Donald C. D.; Yung, Kar W.; Cheng, David C.; Hagen, Frank A.; Chang, Ming U.; Novak, III, John I., Coherent synchronization of code division multiple access signals.
Su-Won Park KR; Young-Ky Kim KR; Jae-Min Ahn KR; Jae-Yoel Kim KR; Hee-Won Kang KR, Gated transmission in control hold state in CDMA communication system.
Lundby, Stein A.; Razoumov, Leonid; Bao, Gang; Wei, Yongbin, Method and apparatus for determining a data rate in a high rate packet data wireless communications system.
Padovani, Roberto; Bender, Paul E.; Black, Peter J.; Grob, Matthew S.; Hinderling, Jurg K.; Sindhushayana, Nagabhushana T.; Wheatley, III, Charles E., Method and apparatus for high rate packet data transmission.
Padovani, Roberto; Bender, Paul E.; Black, Peter J.; Grob, Matthew S.; Hinderling, Jurg K.; Sindhushayana, Nagabhushana T.; Wheatley, III, Charles E., Method and apparatus for high rate packet data transmission.
Padovani, Roberto; Bender, Paul E.; Black, Peter J.; Grob, Matthew S.; Hinderling, Jurg K.; Sindhushayana, Nagabhushana T.; Wheatley, III, Charles E., Method and apparatus for high rate packet data transmission.
Padovani, Roberto; Bender, Paul E; Black, Peter J.; Grob, Matthew S.; Hinderling, Jurg K.; Sindhushayana, Nagabhushana T.; Wheatley, III, Charles E., Method and apparatus for high rate packet data transmission.
Ahn, Jae-Min; Yoon, Soon-Young; Kang, Hee-Won; Kim, Young-Ky, Method and apparatus for initializing a packet traffic channel in a communication system.
Breit, Gregory Alan; Vermani, Sameer; Abraham, Santosh Paul; Sampath, Hemanth, Physical layer metrics to support adaptive station-dependent channel state information feedback rate in multi-user communication systems.
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