Abstract: A module formed by an array of pipes is provided for installation in front of existing radar and sonar transducers. A preferred array is formed by a section of honeycomb material in which each pipe has a hexagonal cross section and is mounted in an insulating sheath. Each pipe acts as a radiator of energy from a transducer that combine in phase to produce a beam narrower than the beam from the transducer. The module is effective to improve the range and resolution of forward-looking radar and sonar devices.