Patent GB-867660-A (GB)
Title: Improvements in or relating to transmitter-receiver switches
IPC: H01J17/04
Filed: 1956-05-02
Abstract: 867,660. Combined radio frequency transmitting and receiving systems. COMPAGNIE GENERALE DE TELEGRAPHIE SANS FIL. May 21, 1956 [May 9, 1956], No. 13614/56. Class 40(5) [Also in Group XL(b)] A TR switch system comprises one or more pairs of rectangular waveguides, each pair being coupled together by a directional coupling arranged in a common wall of the pair, and an equal number of pairs of rectangular waveguides filled with an ionisable gas, each pair being coupled together by a directional coupling arranged in a common wall of the pair, each gas-filled waveguide being provided with a total coupling aperture consisting of a window closed by a dielectric adjacent a coupling aperture in one of the non-gas-filled waveguides. In an arrangement using one pair of each type of waveguide, Fig. 3 shows a cross-section of the two air-filled waveguides and Fig. 4 a cross-section of the gas-filled waveguides. In Fig. 3 the two waveguides 4, 5 have a common wall in which is arranged two openings 10, 11 dimensioned to form 3dB directional couplings; the left end of waveguide 4 is coupled to a transmitter, the right end of waveguide 5 is coupled to an aerial, and the other two ends of the guides are closed by absorber loads 12, 13. Two windows 8, 9 in the sides of the waveguides are arranged adjacent the two windows 14, 15 (Fig. 4) of the gas-filled waveguide 6, 7 which are coupled together by a 3dB directional coupling 20. The waveguides 6, 7 are provided with absorber loads 17, 18, 19 at three of their ends, and the other end is coupled through a resonant window 16 to a receiver; the guides are filled with an ionisable gas such as a mixture of argon and water vapour. During transmission energy fed into waveguide 4 divides at the junction 10 into the two waveguides 4, 5, and in passing the windows 8, 9 causes ionisation in the waveguides 6, 7 which prevents any appreciable passage of energy into these waveguides. At the junction 11 further energy is transferred into waveguide 5 and the output of this waveguide is fed to an aerial (not shown). During reception, energy received by waveguide 5 is divided at junction 11 between the two waveguides 4, 5 and passes through the windows 8, 9 into the gas-filled waveguides 6, 7, and thence through the junction 20 and window 16 to a receiver (not shown). The waveguides 4 and 5 may be coupled to each other through their narrow sides and to waveguides 6 and 7 through their broad sides or viceversa. In an alternative arrangement, Figs. 6 and 7 (not shown), waveguides 4 and 5 are coupled together by a single directional coupling and are terminated by reflectors, the couplings to the transmitter and to the aerial being adjacent each other. Figs. 8 and 9 show an arrangement using two pairs of waveguides. In Fig. 8, the transmitted power is divided by a coupling 25 into two systems similar to that of Fig. 3 and the power is recombined by a coupling 41 before passing to the aerial. The corresponding arrangement. of gas-filled guides is shown in Fig. 9, the two pairs of guides being connected together by a coupling 62.