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Constant Amplitude Zero Autocorrelation Waveform
In signal processing, a Constant Amplitude Zero AutoCorrelation waveform (CAZAC) is a periodic complex number, complex-valued signal (electrical engineering), signal with modulus one and out-of-phase periodic (cyclic) autocorrelations equal to zero. CAZAC sequences find application in wireless communication systems, for example in 3GPP Long Term Evolution for synchronization of mobile phones with base stations. Zadoff–Chu sequences are well-known CAZAC sequences with special properties. Example CAZAC Sequence For a CAZAC sequence of length N where M is relatively prime to N the kth symbol u_k is given by: Even N u_k = \exp \left(j \frac \right) Odd N u_k = \exp \left(j \frac \right) Power Spectrum of CAZAC Sequence The power spectrum of a CAZAC sequence is flat. If we have a CAZAC sequence the time domain autocorrelation is an impulse : r(\tau)=\delta(n) The discrete fourier transform of the autocorrelation is flat : R(f) = 1/N Power spectrum is related to autocorre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Processing
Signal processing is an electrical engineering subfield that focuses on analyzing, modifying and synthesizing ''signals'', such as audio signal processing, sound, image processing, images, and scientific measurements. Signal processing techniques are used to optimize transmissions, Data storage, digital storage efficiency, correcting distorted signals, subjective video quality and to also detect or pinpoint components of interest in a measured signal. History According to Alan V. Oppenheim and Ronald W. Schafer, the principles of signal processing can be found in the classical numerical analysis techniques of the 17th century. They further state that the digital refinement of these techniques can be found in the digital control systems of the 1940s and 1950s. In 1948, Claude Shannon wrote the influential paper "A Mathematical Theory of Communication" which was published in the Bell System Technical Journal. The paper laid the groundwork for later development of information c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
