Planar channelized log-periodic antenna

We present the design, simulation, and measurement of a dual linearly polarized log-periodic antenna matched to a log-periodic channelizing filter through a tapered microstrip balun. The design can be implemented monolithically. A prototype of the channelized antenna, which operates over 1 - 5 GHz, is realized on printed circuit board with a dielectric constant of 4.5. Because we designed the antenna and channelizer with the same log-period (τ = 1.2) the variation in antenna impedance and radiation pattern is theoretically the same over every channel (Δv/v - 0.2). The channel-averaged radiation patterns show less variation from channel to channel (1.64 - 5.26 GHz) than do radiation patterns sampled over a single log-period in frequency (4.39 - 5.26 GHz). We are developing this channelized log-periodic antenna as a scale model of a polychromatic millimeter-wave pixel for an array receiver of transition-edge sensor bolometers. We are constructing such receivers to measure the polarization of cosmic microwave background radiation.