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[Effective directivity by DSP]

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[Overlap in Phase Difference] [Elliptical Polarization]

[Phase Selectivity and Directivity] [Overlap in Frequency]

[Noise Sources] [Consequences of Noise] [Noise Reduction]

[DSP Functionality] [Limitations]

[Results and Audio Samples]

 

Noise Reduction

 

Antenna amplifier noise and receiver noise can be found over the entire 360 phase difference. Atmospheric noise and man-made noise appear over a smaller range, defined by the distance between the antennas and the operating frequency. The amount of noise we pass is determined by the part we pass via the phase window. The width and form of this window determines how much noise is effectively passed. But also the amplitude ratios of the various noise sources is of influence, as it determines the distribution of the phase difference over 360.

For the antenna amplifier noise and the receiver noise, reduction can increase considerably. A phase window of 45 will already show a reduction of 9 dB. A local interfering source, which is received by only one of the loop antennas, will also undergo similar reduction. Atmospheric and manmade noise will be reduced less. This noise is not distributed over the entire 360 but is concentrated within a smaller area.

 

 

Last update: September 24, 2006

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