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公开(公告)号：EP0515675B1
公开(公告)日：1998-07-22
申请号：EP92903696.0
申请日：1991-12-10
CPC分类号： H04W52/343 , G01S5/0036 , G01S5/14 , G01S13/82 , H04B1/707 , H04B7/18547 , H04J13/00 , H04W52/346
摘要： A spread spectrum communications system for use over a communication channel, including a transmitter-generic-chip-code generator (101), a transmitter-message-chip-code generator (102), an EXCLUSIVE-OR gate (103), a combiner (104), a transmitter (107), a receiver-generic-chip-code generator (121), a receiver-generic mixer (123), a generic-bandpass filter (125), a receiver-message-chip-code generator (122), a receiver-message mixer (124), a message-bandpass filter (126), and a synchronous detector (139). The transmitter-generic-chip-code generator (101) generates a generic-chip-code signal and the transmitter-message-chip-code generator (102) generates a message-chip-code signal. The EXCLUSIVE-OR gate (103) spread-spectrum processes message data with the message-chip-code signal to generate a spread-spectrum signal. The combiner (104) combines the generic-chip-code signal with the spread-spectrum signal. The transmitter (107) transmits the combined generic-chip-code signal and spread-spectrum signal, on a carrier signal (108) over the communications channel as a spread-spectrum-communications signal. The receiver-generic-chip-code generator (121) generates a replica of the generic-chip-code signal. The generic mixer (123) recovers the carrier signal from the spread-spectrum-communications signal. The receiver-message-chip-code generator (122) generates a replica of the message-chip-code signal. The receiver-message mixer (124) despreads the spread-spectrum-communications signal as a modulated-data signal. The tracking and acquisition circuit (121) uses the recovered carrier signal for synchronizing the replicas of the generic-chip-code signal to the recovered carrier signal. The synchronous detector (139) synchronously demodulates the modulated-data signal as received data.
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公开(公告)号：EP0515624B1
公开(公告)日：1998-08-12
申请号：EP92900991.8
申请日：1991-11-14
IPC分类号： H04B1/66
CPC分类号： H04B1/7113 , H04B1/709 , H04B1/7117
摘要： An apparatus for adapting to receive a particular path, having the greatest amplitude, of a spread-spectrum signal with multipath. The spread-spectrum signal is modulated by a chip-code. A chip-code generator (401) generates a chip-code signal having the same chip-code as the spread-spectrum signal. A plurality of shift registers shift the chip-code signal by a plurality time delays. First and second ring counters (405, 409) generate first and second sequencing signals for controlling first and second switching devices (407, 411). The first switching device successively switches between a plurality of taps of the shift registers in a direction of increasing or decreasing delays for generating the chip-code signal with the first time delay. The second switching device successively switches between the plurality of taps of the shift registers in a direction of increasing or decreasing delays for generating the chip-code signal with a second time delay. A first correlator correlates the spread-spectrum signal received at the input with the chip-code signal with the first time delay. A second correlator correlates the spread-spectrum signal received at the input with the chip-code signal with the second time delay. A comparator generates first and second comparator signals by comparing the outputs of the first correlator and the second correlator.
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公开(公告)号：EP0767976A1
公开(公告)日：1997-04-16
申请号：EP95926635.0
申请日：1995-06-16
CPC分类号： H04B7/0894 , G01S3/42 , H01Q3/22 , H01Q3/26 , H01Q3/2605 , H01Q3/2682 , H04B1/1081 , H04B1/69 , H04B1/707 , H04B7/084 , H04L1/06
摘要： A phased array spread-spectrum system maximizes signal strength of a spread-spectrum signal with multipath. RF/IF section (21) receives a plurality of spread-spectrum signals. RF/IF section (22) receives a plurality of phased versions of the plurality of spread-spectrum signals. Digital delay devices (27, 28) delay the received spread-spectrum signals with respect to their phased versions by a plurality of delays. Summers (29, 30) combine the delayed spread-spectrum signals and their phased versions as a plurality of combined signals. Despreader (31) despreads the combined signals as a plurality of despread signals. Magnitude device (32) generates a plurality of magnitude values from the despread signals. Shift register (33) stores a plurality of previous-magnitude values and present-magnitude values previously and presently generated by the magnitude device (32). Comparator (34) compares the previous-magnitude values to the present-magnitude values and outputs a plurality of comparison signals. Digital delay devices (27, 28), responsive to the comparison signals, lengthen or shorten the plurality of delays.
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公开(公告)号：EP0772928B1
公开(公告)日：2002-09-18
申请号：EP95927544.7
申请日：1995-07-05
CPC分类号： H04B1/71075 , H04B1/709 , H04B1/7093
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公开(公告)号：EP0767993A1
公开(公告)日：1997-04-16
申请号：EP95925568.0
申请日：1995-06-16
CPC分类号： H04W88/06 , H04B1/707 , H04B1/7093 , H04M3/56 , H04M2207/18 , H04W72/005 , H04W84/20 , H04W88/08
摘要： A conference calling spread-spectrum communications system and method using a plurality of spread-spectrum units, any one of which may serve as the base station and where the base station may be changed upon demand. Each spread-sprectrum unit includes a base subunit (11-21), a remote subunit (40), and a command subunit (41-44). An operator may initiate from the command subunit (41-44), a command signal to activate the base subunit (11-21). Accordingly, upon initiating the command signal, the command signal is broadcast to the plurality of spread-spectrum units. At the respective remote subunit (40), in each of the spread-spectrum units, the command signal is received, and in response to receiving the command signal, the remote subunit (40) is activated.
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公开(公告)号：EP0514539B1
公开(公告)日：2000-07-05
申请号：EP92903307.4
申请日：1991-12-03
IPC分类号： H04J13/00
CPC分类号： H04W52/343 , G01S5/0036 , G01S5/14 , G01S13/82 , H04B1/71 , H04B1/7102 , H04B7/18547 , H04B7/216 , H04B7/2628 , H04B7/2631 , H04J13/00 , H04W16/02 , H04W52/346
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公开(公告)号：EP0772928A1
公开(公告)日：1997-05-14
申请号：EP95927544.0
申请日：1995-07-05
CPC分类号： H04B1/71075 , H04B1/709 , H04B1/7093
摘要： A spread-spectrum CDMA interference canceler for reducing interference in a DS/CDMA receiver having N chip-code channels. The interference canceler includes a plurality of correlators (54, 64, 74), a plurality of spread-spectrum-processing circuits (55, 65, 75), subtracting circuits (150), and channel correlators (146). Using a plurality of chip-code signals generated from chip codeword signal generators (52, 62, 72), the correlators (54, 64, 74) despreads the spread-spectrum CDMA signal as a plurality of despread signals. The plurality of spread-spectrum-processing circuits (55, 65, 75) uses a timed version of the plurality of chip-code signals generated from the delay devices (53, 63, 73), for spread-spectrum processing the plurality of despread signals. For recovering a code channel using an ith chip-code-signal, the subtracting circuits (150) subtracts from the spread-spectrum CDMA signal, each of the N-1 spread-spectrum-processed-despread signals thereby generating a subtracted signal. The channel-correlator (146) despreads the subtracted signal.
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公开(公告)号：EP0767993B1
公开(公告)日：2003-08-13
申请号：EP95925568.8
申请日：1995-06-16
CPC分类号： H04W88/06 , H04B1/707 , H04B1/7093 , H04M3/56 , H04M2207/18 , H04W72/005 , H04W84/20 , H04W88/08
摘要： A conference calling spread-spectrum communications system and method using a plurality of spread-spectrum units, any one of which may serve as the base station and where the base station may be changed upon demand. Each spread-sprectrum unit includes a base subunit (11-21), a remote subunit (40), and a command subunit (41-44). An operator may initiate from the command subunit (41-44), a command signal to activate the base subunit (11-21). Accordingly, upon initiating the command signal, the command signal is broadcast to the plurality of spread-spectrum units. At the respective remote subunit (40), in each of the spread-spectrum units, the command signal is received, and in response to receiving the command signal, the remote subunit (40) is activated.
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公开(公告)号：EP0767976B1
公开(公告)日：2002-08-28
申请号：EP95926635.4
申请日：1995-06-16
CPC分类号： H04B7/0894 , G01S3/42 , H01Q3/22 , H01Q3/26 , H01Q3/2605 , H01Q3/2682 , H04B1/1081 , H04B1/69 , H04B1/707 , H04B7/084 , H04L1/06
摘要： A phased array spread-spectrum system maximizes signal strength of a spread-spectrum signal with multipath. RF/IF section (21) receives a plurality of spread-spectrum signals. RF/IF section (22) receives a plurality of phased versions of the plurality of spread-spectrum signals. Digital delay devices (27, 28) delay the received spread-spectrum signals with respect to their phased versions by a plurality of delays. Summers (29, 30) combine the delayed spread-spectrum signals and their phased versions as a plurality of combined signals. Despreader (31) despreads the combined signals as a plurality of despread signals. Magnitude device (32) generates a plurality of magnitude values from the despread signals. Shift register (33) stores a plurality of previous-magnitude values and present-magnitude values previously and presently generated by the magnitude device (32). Comparator (34) compares the previous-magnitude values to the present-magnitude values and outputs a plurality of comparison signals. Digital delay devices (27, 28), responsive to the comparison signals, lengthen or shorten the plurality of delays.
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公开(公告)号：EP0515610B1
公开(公告)日：1998-08-05
申请号：EP92900295.4
申请日：1991-11-14
IPC分类号： H04K1/00
CPC分类号： H04W52/221 , H04B1/707 , H04B1/7075 , H04W52/146 , H04W52/225 , H04W52/228 , H04W52/245 , H04W52/246 , H04W52/52
摘要： An apparatus for adaptive-power control of a spread-spectrum transmitter of a mobile station operating in a cellular-communications network using spread-spectrum modulation. A base station transmits a generic spread-spectrum signal and an APC information-data signal. A mobile station has an acquisition circuit (101, 102, 103) for acquiring and decoding the generic spread-spectrum signal, a detector (104) for detecting a received power level of the generic spread-spectrum signal, a decoder (105) for decoding the APC-data signal as a threshold, a differential amplifier (106) for generating a comparison signal by comparing the received power level to the threshold, a transmitter (112) for transmitting a transmitter spread-spectrum signal, an antenna, and a variable-gain device (111) responsive to the comparison signal indicating an increase or decrease for adjusting a transmitter-power level of the transmitter spread-spectrum signal.
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