Small coupled double loop antennas for dual band GPS arrays

Small footprint coupled double loop (CDL) antennas are presented for dual band anti-jam GPS arrays. Miniaturization is achieved by employing a readily available ε_r=9.8 substrate and lumped coupling capacitors. A CDL GPS antenna prototype having 1"×1" (λ₀/9.6×λ₀/9.6 at L2 band) footprint over a 0.5" thick 1.6"×1.6" substrate is shown to operate with 3.8dB and 3.3dB measured gains at the L2 and L1 bands, respectively. To realize the smallest possible GPS array, the performance parameters of the CDL antenna are investigated in detail as a function of its substrate size.