The radiation characteristics of a zig-zag antenna

The radiation properties of a single zig-zag antenna are reported. This is a special type of broad-band traveling-wave antenna which, when properly designed, produces a strong axial beam of radiation. The radiation pattern has a half-power beamwidth of 22\deg in the E plane and 28\deg in the H plane; the corresponding sidelobe ratios are 10.5 db and 17.5 db down, respectively, in the two planes. Approximate expressions for the radiation fields are also given and compared with the experimental values. The broad-band property of the antenna is studied by measuring the radiation patterns over a range of frequencies. The performance of the antenna is compared with the Yagi antenna. The high directivity of the antenna can be utilized advantageously in the vhf and uhf ranges. The results of impedance measurement also are reported.