Method of determining the location of the FFT window and the delay spread for the platinum broadcast channel estimator

A channel estimation method, comprising:

• receiving an RF signal in an RF receiver;
• downconverting the received RF signal to obtain a received IF signal in an IF receiver;
• converting the received IF signal into a digital signal in an analog to digital converter;
• determining a FFT window position of the converted digital signal in a digital signal processor;
• and
• calculating a delay spread, wherein said step of determining a FFT window position comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an earliest path hypothesis for each said tap with a first threshold multiplied by a mean average energy over all said taps;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A receiver to estimate a channel, comprising:

• an RF receiver having an input and an output;
• an IF receiver having an input and an output, wherein said input is operably connected to an output of said RF receiver;
• an analog-to-digital converter having an input and an output, wherein said input is operably connected to said output of said IF receiver;
• a decoder having an input and an output;
• and
• a processor having an input and an output, wherein said input is operably connected to said output of said analog-to-digital converter and said output is operably connected to said input of said decoder and said processor comprises
• memory, and
• software comprising instructions stored in said memory,
• wherein said receiver is adapted to execute said instructions stored in said memory comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an average energy of each said tap with a first threshold;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A receiver to estimate a channel, comprising:

• an RF receiver having an input and an output;
• an IF receiver having an input and an output, wherein said input is operably connected to an output of said RF receiver;
• an analog-to-digital converter having an input and an output, wherein said input is operably connected to said output of said IF receiver;
• a decoder having an input and an output;
• and
• a processor having an input and an output, wherein said input is operably connected to said output of said analog-to-digital converter and said output is operably connected to said input of said decoder and said processor comprises
• memory, and
• software comprising instructions stored in said memory,
• wherein said receiver is adapted to execute said instructions stored in said memory comprising:
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of an FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an earliest path hypothesis for each said tap with a first threshold multiplied by a mean average energy of all said taps;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A processor to estimate a channel, comprising:

• memory;
• and
• software comprising instructions stored in said memory, wherein said processor is adapted to execute said instructions stored in said memory comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an average energy of each said tap with a first threshold;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and defining said FFT window position.

A processor to estimate a channel, comprising:

• memory;
• and
• software comprising instructions stored in said memory, wherein said processor is adapted to execute said instructions stored in said memory comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an earliest path hypothesis for each said tap with a first threshold multiplied by a mean average energy over all said taps;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A receiver means to estimate a channel, comprising:

• an RF receiver means having an input and an output;
• an IF receiver means having an input and an output, wherein said input is operably connected to an output of said RF receiver means;
• an analog-to-digital converter means having an input and an output, wherein said input is operably connected to said output of said IF receiver means;
• a decoder means having an input and an output;
• and
• a processor means having an input and an output, wherein said input is operably connected to said output of said analog-to-digital converter means and said output is operably connected to said input of said decoder means and said processor means comprises
• memory means, and
• software comprising instructions stored in said memory means, wherein said receiver means is adapted to execute said instructions stored in said memory means comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an average energy of each said tap with a first threshold
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

The receiver means according to claim, wherein said defining said FFT window position instruction comprises:

• defining an earliest path location;
• defining a latest path location;
• setting a starting point of said FFT window to said earliest path location minus a backoff if a difference between said earliest and said latest path locations plus twice said backoff is less than or equal to a cyclic prefix;
• and
• setting a starting point of said FFT window to said earliest path location minus one half of {(a sum of (a cyclic prefix and said earliest path location)) minus (said latest path location)} if said difference between said earliest and said latest path locations plus twice said backoff is greater than said a cyclic prefix.

A receiver means to estimate a channel, comprising:

• an RF receiver means having an input and an output;
• an IF receiver means having an input and an output, wherein said input is operably connected to an output of said RF receiver means;
• an analog-to-digital converter means having an input and an output, wherein said input is operably connected to said output of said IF receiver means;
• a decoder means having an input and an output;
• and
• a processor means having an input and an output, wherein said input is operably connected to said output of said analog-to-digital converter means and said output is operably connected to said input of said decoder means and said processor means comprises
• memory means, and
• software comprising instructions stored in said memory means, wherein said receiver means is adapted to execute said instructions stored in said memory means comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an earliest path hypothesis for each said tap with a first threshold multiplied by a mean average energy over all said taps;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A processor means to estimate a channel, comprising:

• memory means;
• and
• software comprising instructions stored in said memory means, wherein said processor means is adapted to execute said instructions stored in said memory means comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an average energy of each said tap with a first threshold;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A processor means to estimate a channel, comprising:

• memory means;
• and
• software comprising instructions stored in said memory means, wherein said processor means is adapted to execute said instructions stored in said memory means comprising
• determining a FFT window position;
• and
• calculating a delay spread, wherein said determining a FFT window position instruction comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an earliest path hypothesis for each said tap with a first threshold multiplied by a mean average energy over all said taps;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.

A storage medium having stored thereon processor-executable software instructions configured to cause a processor to perform steps comprising:

• determining a FFT window position;
• and
• calculating a delay spread, wherein said step of determining a FFT window position comprises:
• setting an initial position of said FFT window;
• computing an energy for each tap;
• time averaging said energy for each said tap;
• comparing an average energy of each said tap with a first threshold;
• comparing said average energy of each said tap with a second threshold multiplied by a maximum average energy in alias components;
• updating said set of paths if said average energy of said tap is greater than said second threshold multiplied by said maximum average energy in alias components;
• and
• defining said FFT window position.