A partial phase-only nulling (PPON) algorithm has been developed and evaluated on a 496-element monopulse phased array antenna system which employs five-bit phase shifters. By using this PPON algorithm, nulls in the far-field pattern can be steered t o the desired directions for a phased array equipped with low-resolution phase shifters t o perform simultaneous nulling in the sum and two difference patterns in the environment of multiple jammers. Simulated and experimental patterns are illustrated.

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Titanium disilicide ͑TiSi 2 ͒ is a high-melting compound with excellent conductivity, which appears to have potential applications in field-emission. In the present article, TiSi 2 thin film was successfully synthesized on a silicon wafer through an in situ chloride-generated strategy by atmospheric-pressure chemical-vapor deposition. The required titanium chloride-precursor vapor was in situ produced at an elevated temperature by preloading NiCl 2 ·6H 2 O onto Ti powder with anhydrous ethanol. This synthetic strategy avoided inconvenience with the direct usage of titanium halide or titanium powder as delivering gaseous precursors. The field-emission behavior of the sample shows a turn-on field of 7.2 V / m and agrees well with the conventional Fowler-Nordheim theory. No obvious degradation was observed in a life-stability experiment period for over 100 min. The convenient and low-cost preparation of the TiSi 2 thin film and its fine field-emission performance suggest that it can serve as a good candidate for a field emitter.

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