Phase-lock loop with adaptive scaling element

Claim 2

An adaptive closed-loop control system comprising at least one scaling element, means for generating at least one state variable whose value is affected by the scale factor of said scaling element, and means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range, and wherein said adjustment is made over a sequence of steps.

Claim 3

The invention of claim 1 wherein said scale factor is adjusted as a function of the magnitude of said state variable.

Claim 4

The invention of claim 1 wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range.

Claim 5

The invention of claim 2 wherein said adjusting means includes means for adjusting the value of said state variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor.

Claim 6

The invention of claim 4 wherein said adjustment is made over a sequence of steps.

Claim 7

The invention of claim 1 wherein said adjusting means adjusts said scale factor when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said state variable to substantially said desired value.

Claim 8

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, and means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range, and wherein said scale factor is adjusted over a sequence of steps, and means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase.

Claim 9

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, and means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range, and wherein said scale factor is adjusted over a sequence of steps, and means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase.

Claim 12

The invention of claim 8 wherein said scale factor is adjusted as a function of the magnitude of said state variable.

Claim 13

The invention of claim 8 wherein in said adjusting step said scale factor is adjusted when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range.

Claim 14

The invention of claim 9 comprising the further step of adjusting the value of said variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor.

Claim 15

The invention of claim 8 wherein in said adjusting step said scale factor is adjusted when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said state variable to substantially said desired value.

Claim 16

A phase tracking method for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said method comprising the steps of maintaining a state variable representative of said estimate in response to a succession of error signals. scaling said state variable by a scale factor, generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating step including the step of adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, wherein in said adjusting step said scale factor is adjusted when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said variable to substantially said desired value.

Claim 17

A phase tracking method for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said method comprising the steps of maintaining a state variable representative of said estimate in response to a succession of error signals. scaling said state variable by a scale factor, generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating step including the step of adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, wherein in said adjusting step said scale factor is adjusted when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said variable to substantially said desired value.

Claim 18

A phase tracking method for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said method comprising the steps of maintaining a state variable representative of said estimate in response to a succession of error signals, scaling said state variable by a scale factor, generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating step including the step of adaptively adjusting said scale factor exclusively as a function of the value of said state variable, wherein in said adjusting step said scale factor is adjusted when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range, generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, and adjusting the value of said state variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor.

Claim 19

A phase tracking method for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said method comprising the steps of maintaining a state variable representative of said estimate in response to a succession of error signals, scaling said state variable by a scale factor, generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating step including the step of adaptively adjusting said scale factor exclusively as a function of the value of said state variable, wherein in said adjusting step said scale factor is adjusted when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range, generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, and adjusting the value of said state variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor.

Claim 20

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising. means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, and means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and wherein said scale factor is adjusted over a sequence of steps.

Claim 21

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising. means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, and means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and wherein said scale factor is adjusted over a sequence of steps.

Claim 22

The invention of claim 15 further comprising means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase.

Claim 23

The invention of claim 16 wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range.

Claim 24

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, wherein said adjusting means adjusts said scale factor when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said state variable to substantially said desired value.

Claim 25

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, and means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, wherein said adjusting means adjusts said scale factor when said state variable differs from a desired value, the amount of said adjustment being such as to bring the value of said state variable to substantially said desired value.

Claim 26

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, and means for adjusting the value of said state variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor, wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range.

Claim 27

Apparatus for generating an estimate of a frequency offset, said frequency offset being the difference between the frequency of a local carrier signal and the frequency of the carrier of a received signal, said apparatus comprising means for maintaining a state variable representative of said estimate in response to a succession of error signals, means for scaling said state variable by a scale factor, means for generating said frequency offset estimate as a function of the resulting scaled state variable, said estimate generating means including means for adaptively adjusting said scale factor exclusively as a function of the value of said state variable, means for generating said succession of error signals as a function of the difference between the phase of said received signal carrier and an estimate of that phase, and means for adjusting the value of said state variable concurrently with the adjusting of said scale factor, the adjustment to the value of said state variable being reciprocal to the adjustment of said scale factor, wherein said adjusting means adjusts said scale factor when said state variable is outside of a predetermined range of values, the amount of said adjustment being such as to bring the value of said state variable to within said range.