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X-Microwave™ Block-Level Prototyping System Kirt's Cogitations™ #271
In case you don't already know, a grown-up's version of the much-ballyhooed
littleBits electronics building block system is available. Instead of assembling snap-together functional
blocks for making LEDs flash or robotic carts, X-Microwave's system
provides a relatively simple and inexpensive venue for designing and building RF and microwave circuits based on a selection
of component blocks for frequencies ranging from hundreds of kHz to tens of GHz.
As you can see in the X-Microwave video below, functional blocks are screwed to a base plate with
optimized interconnects providing low-VSWR, low-loss interfaces between blocks. Package sides, isolation compartment walls,
and lids complete the system package with coaxial connectors at the I/O ports. The video does not indicate DC supply connections
or RF path bends, but the website documentation shows it. You begin by laying out your complete system using the online
Mechanical Layout Tool (MLT). An online
system simulator (registration required for use) is provided that is powered by Keysight Technologies'
GenesysSpectrasys using s- and x-parameter files.
Once your design is tested and optimized, the building blocks can either be mounted directly into a permanent machined
enclosure or the block functions can be transferred to a custom printed circuit microwave substrate and placed in an enclosure.
I did not see any mention of whether license fees apply for use of circuit blocks in a production environment when transferred
to a custom substrate.
Prices for each functional block range from about $10 for a section of transmission line to $250 for an LO. A 5 GHz
amplifier costs from around
$80 to $150. A 1920 MHz bandpass filter costs $230, but can vary between $25 and $600 depending on your need. The basic
prototyping metal base plate runs $600. Amplifier manufacturers include
RFMD (now Qorvo), and
Hittite (now Analog Devices). Filters manufacturers include Dielectric Labs and Mini-Circuits. Mixers
come from Marki Microwave and Mini-Circuits. Attenuator pads are from Mini-Circuits. Many of the function blocks must be
in-house designs and list no specific manufacturer. Functional block interconnect 'anchors' are $10 apiece, and
coaxial connectors run
from about $10 up to $100. Machined housings with RF connector and control/power feedthrough holes range from $80 to $120. A full
Prototype Station Kit with performance to 67 GHz
with the base plate, test cables, and probes (connectors) costs $2000.
Example X-Microwave parts list for simple frequency downconverter.
If you have a product concept that requires a relatively simple RF section and you do not want to spend potentially tens
of thousands of dollars buying software and paying for prototype iterations, and especially if you do not have an experienced
RF circuit and layout designer on staff, X-Microwave could be exactly what you need for success. University microwave labs
could benefit greatly from such a system. Manufacturers of RF and microwave components - amplifiers, filters, circulators
(none currently in the available parts list), couplers, dividers, oscillators, attenuators, terminations, etc. - might see
this as great opportunity for getting designed into production circuits.
With enough participation, there might even be an enthusiastic X-Microwave user base that can establish open source functional
blocks like the multinational littleBits Community.
X-Microwave Demonstration Video
X-MWblocks (X-Microwave) webcast by Microwave Journal and Keysight Technologies