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US5673267A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of allocating carrier frequencies for simultaneous transmission of a plurality of modulated signals especially on an optical link

Assignee: Alcatel CIT SA
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Filing: 1993-06-03
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Granted: 1997-09-30
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Expires: 2013-06-03
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Abstract

Abstract In a method of allocating carrier frequencies for simultaneous transmission of a plurality of modulated signals the carrier frequencies are chosen to satisfy the equation: f=(2p+1)n±k where "p" is an integer number specific to each carrier frequency, "n" represents a given frequency bandwidth and "k" represents a given frequency bandwidth less than "n" and possibly a null bandwidth. The value of n is chosen to be sufficiently large relative to the width of the frequency channels occupied by the modulated signals that if k≠0 second order composite distortion occurs outside the channels. Alternatively, if n is insufficiently large relative to the width of the channels (or the widest of them if the channels are not all the same width) the capacity of the transmission system is such that second order composite distortion occurring inside the channels is offset sufficiently relatively to the carrier frequency not to disrupt the transmission of the respective signals.

Inventors

  • 👤 Lionel Adnet

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 01:14
CPC Classifications
H; H04; H04J; H04J14/00; H04J14/02; H04J14/0298

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 129 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth.
Claim 2
Independent Claim 129 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth.
Claim 3
Dependent Claim 106 words
The method according to claim 1 wherein a frequency band including said carrier frequencies is divided into a lower band and an upper band, and said carrier frequencies in one of said lower and upper bands are chosen to satisfy the equation: f=( w!2p+1)n±k where k≠0 and said carrier frequencies in the other of said upper and lower bands are chosen to satisfy the equation: f=(2p+1)n in order to reduce or eliminate any disturbances due to second order composite distortion without it being necessary to consider either the ratio of the bandwidth n and the width of said channels or the capacity of the transmission system.
Claim 4
Independent Claim 199 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, and wherein said frequency allocation conforms to the B, G, H and I standards and the allocated frequencies comprise frequencies in the UHF band from 471.25 MHz to 839.25 MHz in 16 MHz steps and frequencies in the VHF band of 55.25 MHz, 71.25 MHz and from 119.25 MHz to 455.25 MHz in 16 MHz steps.
Claim 5
Independent Claim 199 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, and wherein said frequency allocation conforms to the B, G, H and I standards and the allocated frequencies comprise frequencies in the UHF band from 471.25 MHz to 839.25 MHz in 16 MHz steps and frequencies in the VHF band of 55.25 MHz, 71.25 MHz and from 119.25 MHz to 455.25 MHz in 16 MHz steps.
Claim 6
Independent Claim 279 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; wherein a frequency band including said carrier frequencies is divided into a lower band and an upper band; wherein said carrier frequencies in one of said lower and upper bands are chosen with k≠0 and said carrier frequencies in the other of said upper and lower bands are chosen with k=0 so that any disturbances due to second order composite distortion are reduced without consideration of the ratio of the bandwidth n to the width of said channels, and of the capacity of the transmission system; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, said frequency allocation conforms to the L standard, and the frequencies allocated comprise frequencies in the UHF band from 471.25 MHz to 839.25 MHz in 16 MHz steps and frequencies in the VHF band of 56 MHz, 72 MHz and from 120 MHz to 456 MHz in 16 MHz steps.
Claim 7
Independent Claim 279 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; wherein a frequency band including said carrier frequencies is divided into a lower band and an upper band; wherein said carrier frequencies in one of said lower and upper bands are chosen with k≠0 and said carrier frequencies in the other of said upper and lower bands are chosen with k=0 so that any disturbances due to second order composite distortion are reduced without consideration of the ratio of the bandwidth n to the width of said channels, and of the capacity of the transmission system; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, said frequency allocation conforms to the L standard, and the frequencies allocated comprise frequencies in the UHF band from 471.25 MHz to 839.25 MHz in 16 MHz steps and frequencies in the VHF band of 56 MHz, 72 MHz and from 120 MHz to 456 MHz in 16 MHz steps.
Claim 8
Independent Claim 176 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, said frequency allocation must conform to the M standard and the allocated frequencies comprise frequencies of 55.25 MHz, 67.25 MHz, 79.25 MHz and from 115.25 MHz to 643.25 MHz in 12 MHz steps.
Claim 9
Independent Claim 176 words
A method of allocating a plurality of carrier frequencies for simultaneous transmission of a plurality of modulated signals over a plurality of frequency channels in a transmission system, wherein said frequencies are chosen to satisfy the equation: f=(2p+1)n±k where: p is an integer number specific to each carrier frequency; n represents a fixed frequency bandwidth, and either n is greater than a frequency bandwidth of the frequency channels occupied by said modulated signals if said frequency channels are all of the same width, or is greater than the frequency bandwidth of a widest one of said frequency channels if said frequency channels are not all of the same width; and k represents a given frequency bandwidth less than n and is greater than or equal to a null bandwidth; and wherein said modulated signals are television signals transmitted by vestigial sideband amplitude modulation, said frequency allocation must conform to the M standard and the allocated frequencies comprise frequencies of 55.25 MHz, 67.25 MHz, 79.25 MHz and from 115.25 MHz to 643.25 MHz in 12 MHz steps.
Claim 10
Independent Claim 136 words
A method of allocating carrier frequencies to frequency channels for simultaneous transmission of modulated signals in a transmission system, each of said frequency channels having a respective width, said method comprising the steps of: determining whether said frequency channels have an identical respective width; setting, when said frequency channels have said identical respective width, a value n of a fixed frequency bandwidth as being greater than said identical respective width; setting, when said frequency channels do not have said identical respective width, said value n of said fixed frequency bandwidth as being greater than said respective width of a widest one of said frequency channels; assigning to each of said carrier frequencies a respective integer number p; selecting a given frequency bandwidth k wherein 0≦k<n; and allocating each frequency of said carrier frequencies so that f=(2p+1)n±k.
Claim 11
Independent Claim 136 words
A method of allocating carrier frequencies to frequency channels for simultaneous transmission of modulated signals in a transmission system, each of said frequency channels having a respective width, said method comprising the steps of: determining whether said frequency channels have an identical respective width; setting, when said frequency channels have said identical respective width, a value n of a fixed frequency bandwidth as being greater than said identical respective width; setting, when said frequency channels do not have said identical respective width, said value n of said fixed frequency bandwidth as being greater than said respective width of a widest one of said frequency channels; assigning to each of said carrier frequencies a respective integer number p; selecting a given frequency bandwidth k wherein 0≦k<n; and allocating each frequency of said carrier frequencies so that f=(2p+1)n±k.

References Cited (Backward Citations)

US4641318A Cited
US4768187A Cited
US4757495A Cited
US4787094A Cited
US4953156A Cited
US5107360A Cited
US5170413A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-09-29 2001-03-31 2001-09-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-09-29 2005-03-31 2005-09-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-09-29 2009-03-31 2009-09-30 $7700.00 Window Closed / Lapsed

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