As of March, 1997, we have had the OCAR operating for only a few weeks. However this has been enough to get a more accurate model of performance and utility.

To date, we have run a low power beacon, local to the OCAR itself, a distant beacon, CW, narrowband and wideband FM as well as wideband stereo FM through it. This Gain/Loss Model shows signal levels measured for a signal transmitted from 9 miles and received at 13 miles from the OCAR, which were used to arrive at the OCAR range. Cable, filter and estimated absorption losses have been included. These numbers have been confirmed by multiple measurements from different locations using a variety of hardware. At present, our OCAR restores LOS performance only to users closer than 1 mile. It is presently a "1 mile" OCAR. This relatively small range is due to excess absorptive losses at the receive antenna's current position. However, an OCAR is very useful well beyond it's 0 dB (LOS restoration distance) contour and ours is quite useful even at > 10 miles. As we are able to regain the ~10 dB of excess loss due to the receive antenna's current location the OCAR_range will be increased significantly. But whatever the gain, this pattern covers the intended user base quite nicely.

It should be understood that the contours shown are not conventional logarithmic antenna patterns but linear distance contours; users located on the green contour see only a -6 dB performance degradation relative to those on red.

Even with the OCAR operating with slightly low gain, the received signals are strong over a large area with excellent recovered S/N due to the fundamentally good paths provided. Without the OCAR signals can not even be copied in many locations. Narrowband communications with power levels in the microwatt region should be possible. SSB and digital signals (our 230 Kbps tcp/ip radio links) are being experimented with at the moment. We are presently adding a circularly polarized antenna to the 230 kbps digital network gateway node and hope to use the OCAR to pass TCP/IP. When the receive antenna location is improved, use of more than 1 watt by any user in any mode will probably be unnecessary, with the possible exception of color ATV, and then only for more distant stations.