An optical true-time delay beam-forming system using a tunable dispersion compensating module (DCM) for dense-wavelength division modulation (DWDM) and a multiwavelength fiber ring laser for a phased array antenna is proposed. The multiwavelength fiber ring laser has one output that includes four wavelengths; and four outputs that include only single-wavelength. The advantage of such a multiwavelength fiber ring laser is that it minimizes the number of devices in the phased array antenna system. The time delays according to wavelengths, which are assigned for each antenna element, are obtained from the tunable DCM. The tunable DCM based on a temperature adjustable Fabry-Perot etalon is used. As an experimental result, a DCM could be used to obtain the change of the beam angle by adjusting the dispersion value of the DCM at the fixed lasing wavelengths of the fiber ring laser in the proposed optical true-time delay.

We have proposed optical true-time delay beam-forming system using a DCF and a multi wavelength laser for phase array antenna. Total time delay for each wavelength band originated from group delay of a DCF and the rued delay line. As a result, a DCF for 80 kIn NZ-DSF could be used to obtain the radiation angle of 1800 by tuning the multi-wavelengths of laser in the PI'oposed optical true-time delay.

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