Abstract: A material properties detection system (100). The system can include an antenna (120) that is tuned for operation within a frequency band over which the antenna transmits. The system also can include a transmitter (210) that generates electromagnetic energy across the frequency band and forwards the electromagnetic energy to the antenna. An impedance measurement circuit (215) can be provided. The impedance measurement circuit can measure an input impedance of the antenna over the frequency band and generate measured impedance data (225). The system can include a material characterization application (230) that processes the measured impedance data to generate a material characterization for a structure (110) to which the antenna is proximate. The material characterization can include a dielectric constant, a permittivity, a loss tangent and/or a permeability.

Abstract: A controller circuit (107) between a transceiver (104) and an RS232communication port (103) provides wireless communication to a remote unit and includes a transmitting and receiving mode indicator (503), a first delay circuit (506) for delaying a packet of data (501) before being transmitted, a timer (502) counting a period of time during which delaying termination of transmitting mode following a last data bit of the packet of data (501). Further, a receive signal detector (504) produces a carrier detect signal (521) and its delayed version (525) through a second delay (522) when a data packet (520) is received from the transceiver (104), first and second AND gates (523, 528) and a third delay circuit (526) receive signals (525and 520) to produce a reformatted received data packet (529) compatible to the RS232format for input to the RS232communication port (103).

Abstract: An improved RF power amplifier is disclosed whereby a PIN-type diode is utilized to provide temperature tracking for the bias supply. The PIN diode provides proper temperature tracking with the bias supply while exhibiting reduced sensitivity to self-rectification. As a result, the power amplifier's bias supply is more stable and less susceptible to inaccuracies, distortion, and oscillation that may be caused by self-rectification in the presence of high RF fields, especially at UHF and 800 MHz.