Block equalization method and device with adaptation to the transmission channel
OwnerPierre Andre Laurentinventor
Life of this patent
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Abstract
Method and device for the equalization of a signal received by a receiver, said signal comprising at least one known data sequence (or probe) and a data block located between a first Probe n-1 and a second probe Probe n. The method comprises a step of estimation of the phase rotation θ of the signal received between the first probe Probe n−1 positioned before the data block to be demodulated and the second probe Probe n positioned after the data block to be demodulated.
Claims7
1- A method for the equalization of the signal received by a receiver, said signal comprising at least one known data sequence (or probe) and a data block located between a first probe Probe n−1 and a second probe Probe n comprising at least one step for the estimation of the phase rotation θ of the signal received between the start of the data block and the end of the data block.
2- A method according to claim 1 wherein it estimates the phase rotation between the first Probe n−1 positioned before the data block to be demodulated and the second probe Probe n positioned after the data block to be demodulated.
3- A method according to one of the claims 1 and 2 comprising a step in which the impulse response of the channel is estimated, firstly, by using the first Probe n−1 and, secondly, by using the second Probe n and a step in which the difference between these two estimated impulse response values is minimized.
4- A method according to claim 3, wherein the difference between the estimated values of the impulse response of the channel can be expressed for example in the form:
- 34 E = ∑ i = 0 L - 1 | h i ( N ) - ⅇ jθ h i ( - P ) | 2
- and wherein the optimum value of the phase rotation θ is determined as being the argument of the sum of the conjugate products, that is:
- 35 θ = arg ( ∑ i = 0 L - 1 h i ( N ) h i ( - P ) * )
5- A method according to one of the claims 1 and 2 comprising at least the following steps:
- a) estimating the impulse responses h0(t) and h1(t) of the probes positioned on either side of the block of data to be analyzed,
- b) estimating the rotation of the phase, θ,
- c) correcting the phase of the frequency of the signal received, and performing a reverse rotation on the data block and the probes,
- d) again jointly estimating the impulse responses by means of the modified probes,
- e) applying a BDFE type data block equalization algorithm with feedback loop.
6- A use of a method according to one of the claims 1 to 5 to the demodulation of signals received in a BDFE.
7- A device for equalizing at least one signal that has traveled through a transmission channel, said signal comprising at least one data block and several probes located on either side of the data block, wherein the device comprises at least one means receiving the signals and adapted to determining the phase rotation 0 of the signal or signals received, between a first Probe (n−1) located before the data block and a second Probe (n) positioned after the data block, correcting the phase of the received signal, estimating the responses by means of the probes thus modified and applying a BDFE type algorithm.