Project Description

Project Scope
Design, construct, and test a 900-MHz ISM band directional panel antenna built using PCB technology. The antenna should maintain a low VSWR over the entire band and not require tuning. The antenna should be enclosed by a water resistant plastic housing that will be capable of outdoor operation in extreme environmental conditions.

The panel antenna is intended for use with the SEL-3031 Serial Radio Transceiver. The SEL-3031 is a spread-spectrum radio operating in the 900-Mhz industrial, scientific and medical (ISM) band. Currently, the SEL-3031 is being used with several variants of Yagi and Omni-directional antenna. A panel antenna is desired to provide some level of directivity similar to a Yagi antenna but in a more compact package that is easier to mount and has lower wind loading. A panel antenna using PCB construction is also more cost-effective to produce than a Yagi antenna. The antenna will be used almost exclusively outdoors, often mounted to a utility pole near a recloser control or at a substation.

Design Requirements

  • The antenna should be directional to provide high forward gain while preventing adjacent interference.

  • The antenna should be capable of being vertically or horizontally polarized.

  • The antenna should maintain a VSWR of less than 1.5:1 over the entire 902-928 MHz band.

  • The nominal impedance should be 50 Ω.

  • The antenna should not require tuning.

  • The forward gain should be at least 8-10 dBi.

  • The antenna should be constructed using printed circuit board technology.

  • The connector should be of type N, female, with mounting TBD.

  • The back plate should be weather resistant.

  • The housing should be molded plastic, water resistant, and have a low profile.

  • The antenna should have a wind survival of 120 MPH.

  • The antenna should be designed for ease of manufacturing.