Band power computation device and band power computation method

摘要

A band power computation device with which the amount of calculation required to compute channel power is reduced, and with which it is possible to obtain channel power with the same precision as when the channel power is obtained from the entire input signal. With this device, a subspace extraction unit (101) extracts a portion of the input signal. An FFT unit (104) performs a Fourier transformation on the extracted signal, generating a spectrum signal. A power computation unit (105) computes the channel power for each frequency from the spectrum signal. A power generation unit (150) expands the channel power to the same channel power as the channel power computed from the input signal, and smoothes the expanded channel power by performing a calculation sequentially from the highest frequency to the lowest frequency, said calculation using the expanded channel power and a prescribed constant.

主权项

1. A band power calculation apparatus comprising:
an extraction section that extracts part of an input signal; a Fourier transform section that generates a spectrum signal by applying Fourier transform to the signal extracted by the extraction section; a calculation section that calculates channel power at each frequency from the spectrum signal generated by the Fourier transform section; a power generating section that extends the channel power calculated by the calculation section up to channel power equivalent to channel power calculated from the input signal, and sequentially performs calculations using the extended channel power and a predetermined constant from higher frequencies toward lower frequencies to perform smoothing of the extended channel power; and a band power acquiring section that adds up the channel power smoothed by the power generating section to acquire power in a predetermined band.