TRAK offers a broad choice of standard junction and differential 4-port waveguide isolators and circulators for applications including commercial marine radar, air traffic control, airborne satellite communications, missile seekers and space based telecommunications.

Our largest isolators (2200Kg) were produced and supplied for Air Traffic Management systems and are used to this day as part of  the SCOT NATS radar system monitoring transatlantic flights paths. The highest power isolator (750kW CW) supplied is used as part of the JET fusion experiment while the device that has travelled furthest, several billion km at last count,  is still orbiting Saturn aboard the Cassini interplanetary probe.

Device and design choices and trade-offs are governed by a large number of interdependent factors which are used to determine optimal solutions for isolators and circulators.

TRAK has supplied large numbers of space qualified products offering that span the entire 27-31 GHz operating band. Tending to be optimised for low insertion loss and ease of mechanical integration the range includes, WR28 & WR34 hybrid couplers, terminations, transitions to 2.9mm, isolators and circulators. All isolators feature 6W loads as standard and both isolators and circulators are available with any combination of WR28 and WR34 apertures with standard or custom flanges types.

KISS_2 isolators and circulators

Image Courtesy of Thales Alenia Space ©

Operating Band [GHz] Insertion Loss [dB max] Return Loss [dB min] Isolation Loss [dB min] Notes
WR19 47.0 to 52.0 0.20 23.0 23.0 Low Power
WR22 44.0 to 46.0 0.15 23.0 23.0 Low Power
WR28 27.0 to 31.0 0.15 23.0 23.0 Any combination of WR28 & 34
WR34 27.0 to 31.0 0.15 23.0 23.0 Low Power
WR42 18.0 to 22.0 0.20 23.0 23.0 Any combination of WR42 & 51
WR51 18.0 to 22.0 0.15 23.0 23.0 High and Low power designs
WR62 17.3 to 18.4 0.15 23.0 23.0 Low Power
WR75 10.7 to 12.8 0.15 23.0 23.0 High and Low power designs
WR75 12.7 to 14.5 0.15 23.0 23.0 Low Power
WR90 8.90 to 10.3 0.15 23.0 23.0 High and Low power designs
WR112 7.25 to 8.40 0.10 23.0 23.0 Low Power
WR137 5.70 to 6.70 0.15 23.0 23.0 Low Power
WR229 3.40 to 4.20 0.15 21.0 21.0 High Power
WR229 4.40 to 4.90 0.15 23.0 23.0 High Power
Ku-Band Receiver isolators and circulators
Ku-Band Receiver featuring TRAK WR75 waveguide isolator. Image courtesy of Airbus.

Space Applications

Waveguide isolators and circulators for space applications are at the core of TRAK’s capability. With each passing year the demand for waveguide devices for space applications grows just as the demands for ever more stringent electrical specifications and higher average power; trends that when taken together with increasing operating frequency and bandwidth create a constant cycle of product development, improvement and technological innovation.

The devices in the gallery above reflect the breadth of heritage gathered over the past 2 decades that represent the core of TRAK’s space qualification heritage and product development focus.

  • Transitions from coaxial to waveguide: a capability that extends from 1 to 45 GHz in a variety of waveguide heights, connector type and launch characteristics.
  • Integrated assemblies: designed to offer compact and electrical performance advantages.
  • Combiners: balanced hybrid types in WR75 to WR22.
  • High Power Isolators: all satellite transmission bands from C to Ka. Many featuring TRAK’s proprietary thin film termination technology.
isolator and circulator

The Ka-Band 2 channel combiner features TRAK isolators, 2.9mm transitions and 3dB balanced power combiner. The insertion loss through the combiner is 0.4dB (excluding the 3dB loss through the hybrid).

The device was supplied for the ESA Ka-Band telemetry transceiver and will be aboard the SOLAR ORBITER when it launches in 2018.



By Frequency Band *

* FMs supplied to 31st December 2016
Band Circulator FMs Isolator FMs Total FMs
S [WR229] 23 23
C [WR137] 47 47
X [WR112] 12 212 224
X [WR90] 581 56 637
Ku [WR75] 220 1430 1650
Ku [WR62] 447 447
K [WR51] 387 468 855
K [WR42] 403 403
Ka [WR34] 841 841
Ka [WR28] 106 3650 3012
Q [WR22] 419 419
V [WR19] 11 11
Total 1306 8007 9313