Edge equalizer
View Patent ↗To compensate for roll-off while estimating a communication channel, an estimate of the channel is provided using a signal transmitted via the communication channel. The pilot tones positioned along the edges of the estimated channel are divided by the corresponding pilot tones of the received signal to generate a first number of ratios. An algorithm is thereafter applied to the first number of ratios to generate a second number of ratios associated with the non-pilot tones positioned along the edges of the estimated channel. Next, numbers that are inverse of the first and second number of ratios are applied to the pilot and non-pilot tones positioned along the edges of the estimated channel to compensate for the roll-offs in the estimated channel.
1. A method of compensating for roll-off while estimating of a communication channel, the method comprising:
receiving a signal transmitted via the communication channel, the received signal having a frequency spectrum including non-pilot tones and edge pilot tones;
providing an estimate of the channel using the received signal;
dividing the edge pilot tones of the estimated channel by corresponding edge pilot tones of the received signal to generate a first plurality of ratios;
applying an interpolation scheme to the first plurality of ratios to generate a second plurality of ratios associated with the non-pilot tones positioned along the edges of the estimated channel; and
applying inverse of the first and second plurality of ratios to the edge pilot tones and to the non-pilot tones of the edges of the estimated channel to compensate for roll-offs in the estimated channel, wherein the frequency spectrum is predefined.
2. The method of claim 1 wherein said interpolation is linear interpolation.
3. The method of claim 1 wherein the frequency spectrum is dynamically determined.
4. The method of claim 1 further comprising:
interpolating the edge pilot tones to increase a density of the edge pilot tones.
5. A channel estimation block comprising a processor operative to estimate a communications channel said processor adapted to, the channel estimation block comprising:
receive a signal transmitted via the communication channel, the received signal having a frequency spectrum including non-pilot tones and edge pilot tones;
provide an estimate of the channel using the received signal;
divide the edge pilot tones of the estimated channel by corresponding edge pilot tones of the received signal to generate a first plurality of ratios;
apply an interpolation scheme to the first plurality of ratios to generate a second plurality of ratios associated with the non-pilot tones positioned along the edges of the estimated channel; and
apply inverse of the first and second plurality of ratios to the edge pilot tones and the non-pilot tones of the edges of the estimated channel to compensate for roll-offs in the estimated channel, wherein the frequency spectrum is predefined.
6. The channel estimation block of claim 5 wherein said processor further adapted to perform linear interpolation.
7. The channel estimation block of claim 5 wherein the frequency spectrum is dynamically determined.
8. The channel estimation block of claim 5 wherein said processor further adapted to:
increase a density of the edge pilot tones.