| 摘要 |
<p>A surveillance radar for the detection of intrusion has a high sensitivity and selectivity. Such a radar has its antenna circuit formed on a substrate to which transistor circuits are connected. A substrate (100) has a metallised area (121) which covers almost the complete face to leave a narrow elongated area (122) on the symmetrical axis of the substrate. This narrow area is metallised. At the two sides a metallic layer (129) connects the first layer (121) on the antenna side with a ground area on the circuit or reverse side. Two pairs of conductors (124,125,127,128) are extended to form a dipole and are connected to the two metallised areas. Another conductor (123) forms a short circuit across the second metallised area (122) to match the antenna to a transistor on the reverse side.</p> |
