Utilization of acoustic waves for atmospheric studies through echo sounding requires an efficient antenna with high on‐axis gain and suppressed sidelobes. The antenna pattern for a piston source, as it influences the evaluation of the acoustic radar equation, is calculated and the effective gain factor obtained. Existing microwave antennas and optical searchlights have been adapted for acoustic use and their performance measured. A conical horn‐reflector antenna made of fiberglass gives excellent performance in the frequency region 1–5 kHz after being coated with a viscous dampening tar to shorten vibration time. This damping allows reception of weak echoes with minimum delay following the transmission of a high‐power acoustic pulse from the antenna. Septum dampers have been used successfully on parabolic‐dish antennas. Antenna beam patterns have been measured on an outdoor range, with some measurements being made across a canyon to avoid multipath ground‐reflection effects. Mainlobe to 90° sidelobe ratios are 40 to 50 dB. The measured antenna pattern for the horn‐reflector antenna agrees closely with predictions for a perfect piston source. The parabolic‐dish antennas produce a more complex diffraction pattern. Absorbing cylindrical antenna enclosures have been found effective in further reducing sidelobe reception by 10 to 20 dB, in agreement with predictions. Attention to antenna design allows acoustic echo‐sounder operation in a noisy urban environment, and keeps noise pollution from the sounder pulses below the annoyance threshold.