The synaptic antenna for reconfigurable array applications-description

Dempsey, R.C.; Bevensee, R. M.

doi:10.1109/aps.1989.134801

Cited by 10 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 shows the carrier distribution (a) if the carrier diffusion length is the same or longer than the substrate thickness and (b) if the carrier diffusion length is shorter than the substrate thickness. The diffusion length becomes approximately 500 µm with 4 10 1 − × sec of carrier lifetime, which is the same as or longer than the substrate thickness. In this case, the optically generated free carriers are used for making the substrate lossy rather than for the conducting channel of a gap.…”

Section: Transmission Lines For the Gap-structure Omsmentioning

confidence: 99%

See 1 more Smart Citation

Analysis of cw-mode optically controlled microwave switch

Kuga

2002

SPIE Proceedings

View full text Add to dashboard Cite

Optical-microwave interaction has been emphasized in optically reconfigurable antenna arrays (ORA) due to the unique advantage that transparency between the optical control signals and microwave signals makes the antenna less susceptible to jamming. One of the important parts in ORA is an optically controlled microwave switch (OMS) as synaptic elements. A gap-structure OMS has been developed as a low-cost and simple device which operates in all frequencies. However, the OMS is essentially operated in a CW-mode, and adverse effects are observed in the CWmode operation. Although a CW-mode OMS has been investigated previously, a detailed analysis has not been reported. In this paper, we present an analysis, and the numerical simulations are compared with the previous measurements.

show abstract

Section: Transmission Lines For the Gap-structure Omsmentioning

confidence: 99%

“…This calculation shows that the gap region becomes a good conductor with the optical power. Other quantities used for the calculation are: 4 10 1× = α cm -1 , 4 10 − = τ sec, S=0.5, and R=0.3. The surface photoconductivity is exponentially decreased from the surface of the substrate to the bottom.…”

Section: Insertion Loss: Simulations and Experimentsmentioning

confidence: 99%

Analysis of cw-mode optically controlled microwave switch

Kuga

2002

SPIE Proceedings

View full text Add to dashboard Cite

show abstract

“…Now the generator impedances in arms (1) and (4) (2) and (3) (1) and (4), 149.6 -j15.1 in legs (2) and (3). Radiation efficiency is 61.4%.…”

Section: Behavior Of Various Antennasmentioning

confidence: 99%

“…All four horizontal arms are X/4 long, modelled by three segments atop the X/4deep substrate in Figure 2 of [2]. The symmetry plane is positioned more practically than in Figure 4 of [2]. Frequency is 1 gHz.…”

Section: Behavior Of Various Antennasmentioning

confidence: 99%

See 1 more Smart Citation

The synaptic antenna for reconfigurable array applications-behavior

Bevensee

Dempsey²

Digest on Antennas and Propagation Society International Symposium

Self Cite

View full text Add to dashboard Cite

The Synaptic antenna is a matrix of thin conductive line segments joined (synapsed) at nodes with photoconducting cells (Photistor') which can be switched on by optical energy alone We report on the input impedance and gain patterns of some horizontal dipole arrays. The broadside 2-dipole array and the collinear dipole pair, with and without parasitic elements. BEHAVIOR OF VARIOUS ANTENNASThe behavior of a Synaptic antenna can be analyzed with a thin-wire version of the computer code NEC 111. The various antennas of interest are constructed by appropriate optical feeds to have the conductive elements shown in Figures 4 and 5 of reference [Z]. A. The Single Horizontal Half-Wave Dipole (a) in Figure 4 [ Z ] .For this antenna M = N = 15. The horizontal arms are X/4 above the ground plane atop the substrate. Frequency was 1 gHz (A = 30 cm). Each segment was either-X/12 long or half as long at the symmetry plane. The voltage generators feeding the two arms produced the current flows indicated by the arrows. The impedance for each generator is 100.1 -j6.7 ohm. Radiation efficiency is 66.7%.The E-plane (@ = 0) relative gain pattern for the major-axis elliptically polarized radiation field and the corresponding H-plane (@ = 90') pattern are shown on the right half of Figure 1. The patterns are symmetric about the 8 = 0' or Z-axis in each plane. Each pattern is relative to the maximum isotropic gain of 5.86 dB shown at 8 = 30', 0 = 90' (or 270 ').Note that the relative gain at 8 = 0 is the same at 0 = 0 and 90 ' because the major-axis radiation field is the same in this direction.The corresponding patterns of the same antenna but without the matrix substrate appear on the lefl side of Figure 1. The impedance for each generator has increased greatly, to $;

show abstract