There were several iterations of this system, known as DARTS, for Digital Amateur Rocket Tracking System. In one of them, I used a frequency-scanned linear array to point the transmit beam in the left-right (azimuth) direction. The frequency of the transmit signal, over about a 50 MHz range, literally controlled the beam direction from left to right.
(UPDATE: I found the original web pages describing the system on the Internet Archive/ Wayback Machine).
The antenna itself is about 7" wide. The coax would be connected at the left edge. The antenna was milled on a T-Tech Quick Circuit circuit board milling machine, just like the one in my lab off to the left of me now.
The antenna is fabricated in 10-mil RT-Duroid material.
|Frequency-Steered Linear Array Beam Antenna, designed by yours truly.|
It was designed using software from a book, CAD of Microstrip Antennas for Wireless Applications by Robert A. Sainati. I actually corresponded by email with Dr. Sainati during the design.
Since the rocket had a transponder on it to bounce the signal back, I didn't have to transmit much power. Plus, as I recall, this array had over 20 dB of gain when pointed straight ahead.
Anyway, I thought y'all might find this interesting.