An approach towards an efficient implementation of a spread spectrum receiver for wireless noncellular home-systems is presented. Whereas conventional receivers apply some filtering after despreading to recover the transmitted data, here a Discrete Fourier transform is applied and its output is redirected to an application specific processor (ASP). As mathematical operations (Fourier transforms...

Rotation Due to the rotation property of the two-dimensional Fourier transform rotation of f (x , y) through an angle & also rotates the spectrum by the same amount. It is also well known that the Fourier spectrum (modulus) is invariant to translation. Now, suppose that we scan the Fourier spectrum IF,(along a circle centered at the origin. If circular sampling of 1 F,I * is used, then by takin...

The Lomb-Scargle periodogram is widely used for the estimation of the power spectral density of unevenly sampled data. A small extension of the algorithm of the Lomb-Scargle periodogram permits the estimation of the phases of the spectral components. The amplitude and phase information is sufficient for the construction of a complex Fourier spectrum. The inverse Fourier transform can be applied...

Fourier methods give excellent frequency estimation performance with either single complex exponentials or long data lengths. For multiple exponentials parametric techniques offer superior resolution. This work examines the signal conditions which determine the choice of a particular method. Equations are developed that describe the Fourier performance with data length, SNR and relative frequen...

The Fourier transform of a dataset apodised with a window function is known as the Gabor transform. In this paper we extend the Gabor transform formalism to the sphere with the intention of applying it to CMB data analysis. The Gabor coefficients on the sphere known as the pseudo power spectrum is studied for windows of different size. By assuming that the pseudo power spectrum coefficients are...

A discrete auditory transform (DAT) from sound signal to spectrum is presented and shown to be invertible in closed form. The transform preserves energy, and its spectrum is smoother than that of the discrete Fourier transform (DFT) consistent with human audition. DAT and DFT are compared in signal denoising tests with spectral thresholding method. The signals are noisy speech segments. It is f...

The JILA multidimensional optical nonlinear spectrometer (JILA-MONSTR) is a robust, ultrastable platform consisting of nested and folded Michelson interferometers that can be actively phase stabilized. This platform generates a square of identical laser pulses that can be adjusted to have arbitrary time delay between them while maintaining phase stability. The JILA-MONSTR provides output pulses...

Discrete cosine transform (DCT) is a special type of transform which is widely used for compression of speech and image. However, its use for spectrum sensing has not yet received widespread attention. This paper aims to alleviate the sampling requirements of wideband spectrum sensing by utilizing the compressive sampling (CS) principle and exploiting the unique sparsity structure in the DCT do...