Under the terms of the contract, financial details of which were not available, EMS is scheduled to deliver a ferrite switch
and driver electronics to meet Thales Alenia Space's 2013 launch date.
The Tandem-rotator Reciprocal ferrite switch
uses 0[degrees] and 90[degrees] total Faraday rotation states to achieve reciprocal connections to the desired ports.
The chief advantages of the ferrite switch
are low insertion loss, high power handling capability and low DC power consumption.
(3-5) One of the more unusual applications was and still is for Dicke Radiometers, (6) where the ferrite switch introduces very little thermal noise.
Diode and mechanical switches have some disadvantages relative to ferrite switches. Diode switches, although faster switching than ferrite junctions, have non-linearities that produce intermodulation products if more than one frequency is present, and do not latch (thus requiring holding current).
Hot switching is possible, as the ferrite switch
will not be damaged by applied power during a switching event, which is on the order of 1 [micro]s.
Low cost, high volume (approximately 1000 units) waveguide circulator ferrite switches
were chosen for the beamforming applications in the MMW region because they are compact; have relatively low losses ([less than] 0.3 dB), long lifetimes ([greater than] 100,000 hours) and reasonably good isolation (approximately 18 to 20 dB); and can tolerate a few watts of CW power easily. The cost of a multijunction ferrite switch
assembly can be as low as $100 per junction. In fact, for high volume commercial applications (such as automotive radar), the cost per junction could be even lower.
The basic circulator design is used for other applications as well, such as ferrite switches
, isolators and phase shifters.