Originally posted Nov 13, 2015
A practical way to revisit decisions about bandwidth and frequency range
No matter how carefully you consider your test equipment choices, your needs will sometimes evolve beyond the capabilities you’ve purchased. You may face a change in standards or technology, or the need to improve manufacturing productivity or margins. Business decisions may take you in a different direction, with some opportunities evaporating and new ones cropping up.
The one thing you can predict with confidence is that your technological future won’t turn out quite the way you expect. Since test equipment is probably a significant part of your capital-asset base, and your crystal ball will always have hazy inclusions, you have to find the best ways to adapt after the fact.
Analyzer software and firmware can certainly help. New and updated measurement applications are often available, tracking standards as they evolve. Firmware and operating-system updates can be performed as needed, though they’re likely more difficult and sometimes more disruptive than just installing an app.
In some cases, however, the new demands may be more fundamental. The most common examples are increasing measurement bandwidth and extended frequency range, both being recurring themes in wireless applications.
Of course, the obvious solution is a new analyzer. You get a chance to polish your crystal ball, make new choices, and hope for the best. Unfortunately, there is not always capital budget for new equipment, and the purchase-and-redeployment process burns time and energy better spent on engineering.
If the analyzer is part of a modular system, it may be practical to change individual modules to get the capability you need, without the expense of complete replacement. Of course, there are still details like capital budget, management of asset numbers and instrument re-calibration.
One approach to upgrading instrument fundamentals is sometimes called a “forklift upgrade,” a term borrowed from major IT upgrades requiring actual forklifts. In the case of test equipment, it’s a tongue-in-cheek reference to the process of lifting up the instrument serial-number plate and sliding a new instrument underneath. For instruments not designed to be upgradable, this term applies pretty well.
Fortunately, the forklift upgrade reflects a prejudice that is out of date for analyzers such as Keysight’s X-Series. Almost any available option can be retrofitted after purchase, even for analyzers purchased years ago.
Fundamental characteristics such as analysis bandwidth, frequency range, and real time spectrum analysis (RTSA) can be added to Keysight X-Series signal analyzers at any time after purchase. This example shows a 160 MHz real-time display and a frequency-mask trigger (inset) on an instrument upgraded from the base 3.6 GHz frequency range.
Upgradability is part of the analyzer design, implemented in several ways. The internal architecture is highly modular, including the RF/microwave front end, IF digitizing, and DSP. The main CPU, disk/SSD memory, and its external digital interfaces are directly upgradable by the user.
For RF engineers, this is the best substitute for time travel. Hardware upgrades include installation, calibration, and a new warranty, with performance specifications identical to those of a new instrument.
There are organizational and process benefits as well, avoiding the need for new instrument purchase approvals and changes in tracking for asset and serial numbers.
If the decisions of the past have left you in a box, check out the new application brief on analyzer upgrades for a way out. If the box you’re in looks more like a signal generator, Keysight has solutions to that problem too.