Abstract: Disclosed is a method, system, and apparatus for transmitting a randomly phase-coded CW waveform in a manner that suppresses signal leakage and enables the recovery of polyphase subcodes advantageous for the purposes of correlation and pulse compression. The CW system transmits and receives a random waveform while concurrently providing properly delayed phase conversion parameters (?i??i) from a corrections generator to various range gates. Each range gate processes any echo returns using a most recent phase conversion parameters (?k??k) provided and correlation of the resulting echo subcodes ?R produce either target indications or noise signals, depending on the most recent phase conversion parameters (?k??k) provided to the range gate. The system may transmit the randomly phase-coded CW waveform while recovering any phase code {?1, ?2, . . . ?N} that lends itself to advantageous pulse compressions.

Abstract: Disclosed is a method, system, and apparatus for transmitting a randomly phase-coded CW waveform in a manner that suppresses signal leakage and enables the recovery of polyphase subcodes advantageous for the purposes of correlation and pulse compression. The CW system transmits and receives a random waveform while concurrently providing properly delayed phase conversion parameters (?i??i) from a corrections generator to various range gates. Each range gate processes any echo returns using a most recent phase conversion parameters (?k??k) provided and correlation of the resulting echo subcodes ?R produce either target indications or noise signals, depending on the most recent phase conversion parameters (?k??k) provided to the range gate. The system may transmit the randomly phase-coded CW waveform while recovering any phase code {?1, ?2, . . . ?N} that lends itself to advantageous pulse compressions.

Abstract: Embodiments in accordance with the invention include a linearly polarized dipole antenna with an unbalanced microstrip feed line. More specifically, embodiments in accordance with the invention utilize a fed dipole connected to a microstrip feed line, and separated a gap distance from a parasitic dipole not connected to the microstrip feed line. When an electrical signal is input to the microstrip feed line, the microstrip feed line creates a current flow in the fed dipole which induces a nearly equal current on the parasitic dipole that is out of phase. The result is a current flow, I, in the same direction in both fed and parasitic dipoles allowing for efficient radiation of the linearly polarized dipole antenna. Embodiments in accordance with the invention eliminate the need for a balun circuit thereby reducing the size, complexity and feed loss of the feed circuit. Embodiments in accordance with the invention are effective for dipoles with relatively small ground planes.

Abstract: Disclosed are process and apparatus for inspecting internal inclusions in internally transmissive substrates. The process involves applying a black coating to one major surface of the substrate, submerging the substrate in a refractive index-matching fluid, and scanning the substrate with a collimated light beam. The scattered light signals produced by the inclusions can be detected by the human eye or by using a light detector. By the use of index-matching fluid and the black coating, the signal-to-noise ratio of the process and apparatus are enhanced. A preferred black coating is one cured from an electron beam or photo polymerizable coating composition applied to the major surface. The process and apparatus are particularly suitable for inspecting internal inclusions in an internally transmissive substrate having considerable amount of surface defects or contoured surface that prevent it from inspection in a gas medium.