June 18, 2013
The Pacific Northwest was the place to be the first week of June if you wanted to learn about the latest high-frequency technologies that extend all the way up to millimeter wave (mm-wave). That was the overwhelming theme at IMS 2013 in Seattle, as the buzz in the aisles and booths centered on higher frequencies and faster data rates, and how to design and test products to meet the associated challenges.
This kind of interest was not overly surprising to us. We have been having discussions with customers for quite some time on the very same topic. Millimeter wave frequencies from 50 GHz to 1 THz are no longer reserved just for the university lab. They are utilized in several commercial communications applications, as well as being used in medical, security, and other applications. Because they are becoming more common, it’s only natural that more engineers from various industries will have questions, especially given the complexities associated with designs at such high frequencies.
Testing at mm-wave frequencies brings new and different measurement challenges, so minimizing measurement uncertainty is critical in the development of these new technologies. That’s why many of the IMS attendees were interested in the various stations of our VectorStar™ Vector Network Analyzer (VNA) system we had in our booth. Here is a brief recap, if you weren’t able to attend the show:
• Broadband System – As you might imagine, since there was strong interest in mm-wave designs, our ME7838A broadband VNA system (figure 1) drew some crowds. Currently available as a 70 kHz to 110 GHz broadband VNA system, at IMS we gave a glimpse of the future with a technology demonstration of a 70 kHz to 145 GHz system. This was configured as an on-wafer device characterization station and created quite a few nods of approval from attendees. The broad frequency coverage of the system allows for highly accurate characterizations to be achieved on broadband devices.
Figure 1
• Noise Figure Measurements – Normally, conducting mm-wave noise figure measurements are not possible in a conventional VNA configuration due to the architecture of the frequency extension modules. At IMS 2013, we showed how that has all changed. A unique compact design was demonstrated whereby the couplers were removed from the modules so that noise figure performance can be optimized. Combining these innovative modules with the performance of the VNA system allows accurate noise figure measurements to be made up to 110 GHz. An informative video on the subject from the show can be found here.
• Signal Integrity – More attendees recognized the importance of measuring as close to DC as possible for highly accurate measurements for use in simulations. At one of our stations, we showed how having broad frequency coverage of 70 kHz to 70 GHz produces a more accurate simulation of the eye diagram to be generated.
We can expect the conversations centered on mm-wave testing to continue, even though we are all back from Seattle. The designs now in the lab will soon be replaced by new ideas that will continue to push the frequency ranges higher. You can rest assured that test systems such as VectorStar will continue to offer the capability necessary to address the testing needs of these designs.
A series of white papers and application notes that address testing broadband and mm-wave designs can be found in the Library tab on this page.
