Log-periodic dipole array
In telecommunication, a log-periodic antenna (LP, also known as a log-periodic array) is a broadband, multielement, unidirectional, narrow-beam antenna that has impedance and radiation characteristics that are regularly repetitive as a logarithmic function of the excitation frequency. The individual components are often dipoles, as in a log-periodic dipole array (LPDA).
The length and spacing of the elements of a log-periodic antenna increase logarithmically from one end to the other.
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