EP0263687A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Spread spectrum communications systems and transmitters and receivers therefor
Assignee: Oki Electric Industry Co Ltd
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Filing: 1987-10-07
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Granted: —
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Expires: 2007-10-07
Abstract
Abstract In a spread spectrum communications system, a filter is inserted in a transmitter and a receiver, respectively. The filter in the transmitter is an FIR filter (14) and the filter (15) in the receiver has a characteristic inverse to that of the FIR filter (14).
Inventors
- 👤 Masaki Kobayashi
- 👤 Yoshio Itoh
- 👤 Hiroji Kusaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 22:44
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/69; H04B1/707
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
A spread spectrum communications system having a transmitter (16) for transmitting a signal resulting from multiplication of a modulated transmit data signal and a modulated spread spectrum code and a receiver (17) for linking to the transmitter by a communication channel and for receiving the signal transmitted from the transmitter and multiplying it by a modulated spread spectrum signal to restore the original transmit data characterised in that an FIR filter (14) is provided in the output section of the transmitter (16) and a filter (15) having a characteristic inverse to that of the FIR filter is provided in the input section of the receiver (17).
Claim 2
Dependent Claim
106 words
A spread spectrum communications system having a transmitter (16) for transmitting a signal resulting from multiplication of a modulated transmit data signal and a modulated spread spectrum code and a receiver (17) for linking to the transmitter by a communication channel and for receiving the signal transmitted from the transmitter and multiplying it by a modulated spread spectrum signal to restore the original transmit data characterised in that an FIR filter (14) is provided in the output section of the transmitter (16) and a filter (15) having a characteristic inverse to that of the FIR filter is provided in the input section of the receiver (17).
Claim 3
Dependent Claim
18 words
A spread spectrum communications system according to claim 1 in which the filter (15) is an IIR filter.
Claim 4
Dependent Claim
50 words
A spread spectrum communications system according to claim 2 in which the IIR filter (15) has the same order as the FIR filter (14) and coefficients of the multipliers of the IIR filter (15) have the same values as the coefficients of the corresponding multipliers in the FIR filter (14).
Claim 5
Dependent Claim
37 words
A spread spectrum communications system according to claim 1 in which the FIR filter (14) incluides multipliers and the coefficients thereof are so determined that average power of a signal output from the FIR filter is minimized.
Claim 6
Dependent Claim
43 words
A transmitter for a spread spectrum communications system characterised in that an FIR filter (14) is provided in the output section of the transmitter (16) for permitting signal reception by a receiver (17) having an inverse characteristic filter (15) in its input section.
Claim 7
Dependent Claim
43 words
A transmitter for a spread spectrum communications system characterised in that an FIR filter (14) is provided in the output section of the transmitter (16) for permitting signal reception by a receiver (17) having an inverse characteristic filter (15) in its input section.
Claim 8
Dependent Claim
42 words
A receiver for a spread spectrum communications system characterised in that an FIR inverse filter (15) is provided in the input section of the receiver (17) for permitting signal reception from a transmitter (16) having an FIR filter in its output section.
Claim 9
Dependent Claim
42 words
A receiver for a spread spectrum communications system characterised in that an FIR inverse filter (15) is provided in the input section of the receiver (17) for permitting signal reception from a transmitter (16) having an FIR filter in its output section.
References Cited (Backward Citations)
No citation records indexed.
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