Patent GB-1297153-A (GB)
IPC: H01Q3/26
Filed: 1969-10-16
Abstract: 1297153 Matching and phase changing TOKYO SHIBAURA ELECTRIC CO Ltd 16 Oct 1969 [16 Oct 1968 21 Oct 1968 (4) 7 March 1969] 50887/69 Heading H1W [Also in Division H4] A phased aerial array comprises a plurality of equally spaced aerial elements 33 1 , 33 2  ... 33 m , Fig. 5, each of which is connected by an individual feeder to a junction box 32, which is supplied by a source 31 through an impedance matching network 35. In each of the said feeders, except that to the element 33 1 , is inserted a respective impedance transforming network 34 1 , 34 2  ... 34 m-1 . Said networks satisfy stated mathematical relationships and may each comprise two quarter-wavelength sections of transmission line in series having a central reactive stub line and either one reactive stub line at the load end of the network (Fig. 6, not shown) or reactive stub lines at each end of the network (Fig. 7, not shown). The reactive stub lines comprise electronically controlled elements whereby the characteristics of said stub lines may be changed to determine the phase and amplitudes of the currents fed to the aerial elements and so effect steering of the beam radiated by the array. One form of stub line comprises a quarter wavelength two-wire line with variable capacitance diodes across each end, an adjustable bias means being associated with each diode (Fig. 8, not shown). In another arrangement, a line is mounted above a ground plane, and individually controlled switching diodes which are spaced along the line allow a short-circuit to be made where required (Fig. 11, not shown). In other similar arrangements, the lengths of line between the switching diodes contain # or bridged-T inductor/capacitor sections (Figs. 12A, 12B, not shown). Another form of stub line is shown in Fig. 17, and comprises four quarter-wavelength sections in series. The first section, at the input end, of the stub line, consists of a pair of coupled single-wire lines, one of which is connected at the near end through a variable capacitance diode Z, to ground, and at the far end directly to ground. The second section is a single-wire line, and the third section consists of a pair of coupled single-wire lines. One line of the third section has its near end disconnected and its far end connected to ground through a variable capacitance diode Z 2  and also through a single-wire line which constitutes the fourth section. A form of stub line is also described which is equivalent to a flattened loop of coaxial line in which two sideby-side outer conductors are merged into a common outer conductor 51 1 , Fig. 10 there being two inner conductors 51 2 , 51 3  within, which are sectionalized by means of respective blocking capacitors C 11 , C 12  &c. and C 21 , C 22  &c. PIN diodes D 11 , D 12  &c. are connected across the inner conductors in alternate sections and permit a short-circuit to be made between said inner conductors where required. Pairs of PIN diodes (D 21 , D 21 ), (D 22 , D 22 ) are connected between the inner conductors and the common outer conductor in the other alternate sections, and permit short circuits to be made between said inner conductors and the outer conductor where required.