Page 212 - Satellite Communications, Fourth Edition

192 Chapter Six

225 45 90 180

Driver Driver Driver Driver
rf rf

Logic
lines
(a)

5 6

1 3
27
2

4
30
(b)

Nominal phase state LEAD connections
cont. pl. 1 cont. pl. 2 cont. pl. 3
45 + − +
90 − + +
135 + + +
180 − − −
225 + − −
270 − + −
315 + + −
Terminology: “+” - control current “−” - reverse voltage.
(c)
Figure 6.41 Digital switching of phased arrays: (a) 4-bit (Courtesy
of T. J. Braviak. Source: www.kditriangle.com), (b) Ku-band p-i-n
diode (3-bit) phase shifter, (c) the switching logic for (b). (Courtesy
of Michael Parnes. Source: http://www.ascor.eltech.ru/ascor15.htm)