A 390 ps On-Wafer True-Time-Delay Line Developed by a Novel Micro-Coax Technology

Abstract

A CMOS-compatible on-wafer true-time-delay (TTD) line for broadband microwave applications is demonstrated using a novel micro-coax technology. The insertion loss of the developed TTD line is less than 2.55 dB for a constant group delay of 390 ps from dc to 40 GHz, without control power or control voltage. To the best of our knowledge, the fabricated micro-coaxial TTD line provides the best figures-of-merit (FOM) value (0.00641 dB/ps at 40 GHz) among reported on-wafer TTD lines. Index Terms-Broadband, figures-of-merit (FOM), monolithic microwave integrated circuit (MMIC), phase shifters, true-timedelay (TTD) line.

A multi-octave microwave 6-bit true time delay with low amplitude and delay variation in 65 nm CMOS

“…For a wideband system, the phase shifter must be replaced by a TTD (true time delay) component to prevent beam-squinting [1]. As a result, many approaches have been developed for the implementation of TTD [1][2][3][4][5][6][7][8][9][10][11].…”

“…Approaches based on transmission lines [2,3] or artificial transmission lines based on LC structures [4,5] yield large size at 2-18 GHz frequency range and high loss and delay variation over the frequency band. It may become a more attractive solution only at a higher frequency [6,7].…”

A true-time-delay transmit/receive module for X-band subarray phased arrays

“…With the increasing demand of broad bandwidth and wide scanning angle, true time delay (TTD) technique is becoming popular in phased array systems such as active electronically scanned array (AESA) radars [1,2,3,4,5]. Scanning angles of a phased array and a TTD array are implied in (1).…”

Air-gapped microaxial transmission line technology for Si-based microwave integrated circuits

“…The ultra-long microcoaxial TID lines can be formed by using the designed straight and curved bends to connect parallel transmission lines together, as shown in Figure 4. 12 [ 159]. The TID lines are folded into II straight sections linked by either straight bends or curved bends, with dimensions of 1.14 em X 0.…”