A new type of shaped-beam antenna has been studied as a possible candidate for the antenna for the next generation Japanese broadcasting satellite which succeeds BS-2, launched January 23, 1984. The studied antenna employs an offset paraboloidal reflector with elliptical shape, an elliptical corrugated horn and a rectangular one. The studied antenna covers most part of the Japanese main lands with antenna gain of more than 39 dB, Okinawa more than 35 dB and remote islands more than 28 dB. The sidelobe and cross-polar components radiated outside the service area satisfies the WARC-BS on the basis of power flux density on the earth assuming 200 W output power of the transponder.

Performance of self-synchronizing scrambler/descrambler in mobile radio transmission systems is discussed theoretically and experimentally. Multiple-error characteristics in descrambler processing are analyzed in detail.

A self-complementary basis of a finite field corresponds to the orthonormal basis of a vector metric space. This paper presents a theorem that GF (2^4m) has no self-complementary normal bases over GF (2) if m is odd, which was recently conjectured by one of the present authors.

Properties of a semi-insulating film deposited by Ar-Beam Sputtering have been investigated. This film was characterized with a substrate temperature lower than 150 during deposition. It was found that this film was as efficient in achieving breakdown characteristics higher than 400 V as were the conventional films.