Phase control device with a plurality of distributed amplifier structures with switchable active elements for constituting a programmable length line

摘要

The device comprises a multiple structure of distributed amplifiers (AD1, AD2) with switching elements (T1,T2), connected between the gate lines (Lgc1, Lgc2) and the drain lines (Ldc1, Ldc2). At least one switching element is active and controlled as a function of the control bit of the cell by the bias controllers (C1,C2). The active switching element between the gate line and the first drain line (Ldc1) is biased in amplifier mode, and that between the gate line and the second drain line (Ldc2) is biased in holding mode, and vice versa. The input (12) is connected to the gate line, and the output to the input of the next distributed amplifier forms the common gate line (10). The outputs (14,16) of distributed amplifiers as terminals of the drain lines (Ldc1, Ldc2) are connected to a summation device (18) with output (19) connected to a load (21) of 50 Ohm, terminating the line of programmable length for 1 bit. The summation device (18) can be active or passive, and its connection forms an auto-recombining structure. In another embodiment, the device contains two sets of double distributed amplifiers (AD1, AD2) connected in series to form a quadruple distributed amplifier (QAD), an an additional summation device receiving inputs from two summation devices making a line of programmable length for 2 bits. The device comprises a number of simple-structure distributed amplifiers (AD1, AD2, AD3, ...) with the common gate line, connected in series directly or indirectly to form a line of programmable length for several bits. The number of delay states determined by the number of distributed amplifiers determines the number of bits; two for 1 bit, four for 2 bits, etc. The device can contain the gate lines connected via passive delay elements. The active switching element is a transistor (T) of type field-effect, bipolar heterojunction, or analogous. The device can be realised by the monolithic microwave integrated circuit (MMIC) technology, and can operate in a very wide frequency band up to several tens of GHz, e.g. 1-20 GHz.