ccurately convey information. In another part of FTL, highly compartmentalized for security purposes, Louis deRosa headed the R-14 Electronic Warfare Group. Derosa, who ear- lier had collaborated with Busignies and Deloraine, and who had exchanged many friendly arguments with Nathan Marchand concerning the merits of Figure 2.15. Only two copies of Rogoff's secret noise wheel, shown here, were made to support ITT's early research on spread-spectrum systems. The noise wheel con- cept was revived briefly in 1963 when two more wheels were produced and tested in a system at ITT. (Photo from [130], courtesy of ITT.) The Historical Origins of Spread-Spectrum Communications Figure 2.16. ITT's equipment constructed for bench-testing a communication sys- tem based on noise-like carriers stored on wheels. (Photo from [130], courtesy of ITT.) IF correlation (à la Marchand [38]) versus baseband correlation via homo- dyning (deRosa's favorite), held an umbrella contract through Dr. George Rappaport, Chief of the Electronic Warfare Branch at WADC, to pursue a variety of electronic countermeasures and counter-countermeasures. The contract, codenamed Project Della Rosa, spanned the 1947-1951 time frame and, hence, was concurrent with Rogoff's work. The first written indication of deRosa's visualization of an SR-SS tech- nique occurs in one of this prolific inventor's patents, filed in January 1950, with L. G. Fischer and M. J. DiToro [129], and kept under secrecy order for some time. The fine print of this patent calls out the possibility of using an arbitrarily coded waveform generated at the transmitter and an identical, synchronous, locally generated waveform at the receiver to provide a refer- ence for a correlation detector, to reliably recover signals well below the noise level. On August 1, 1950, deRosa gave a laboratory demonstration of Rogoff's noise wheels to visiting U.S. Air Force personnel, with the system extract- ing signals 35 dB below the interfering noise. Later the same month, deRosa and Rogoff produced a secre