  We present a design for an array of kinetic inductance detectors (KIDs)
integrated with phased array antennas for imaging at 150 GHz under high
background conditions. The microstrip geometry KID detectors are projected to
achieve photon noise limited sensitivity with larger than 100 pW absorbed
optical power. Both the microstrip KIDs and the antenna feed network make use
of a low-loss amorphous silicon dielectric. A new aspect of the antenna
implementation is the use of a NbTiN microstrip feed network to facilitate
impedance matching to the 50 Ohm antenna. The array has 256 pixels on a 6-inch
wafer and each pixel has two polarizations with two Al KIDs. The KIDs are
designed with a half wavelength microstrip transmission line with parallel
plate capacitors at the two ends. The resonance frequency range is 400 to 800
MHz. The readout feedline is also implemented in microstrip and has an
impedance transformer from 50 Ohm to 9 Ohm at its input and output.

Instrumentation and Methods for Astrophysics;Instrumentation and Detectors