With the growing need for real-time analysis of complex signals, I recently interviewed Agilent Technologies' Richard Overdorf about the company's new real-time spectrum analysis (RTSA) functionality for its PXA X-series signal analysers.

The biggest news of this announcement is the probability of intercept. When tweaked for real-time spectrum analysis, Overdorf explained that the PXA can detect intermittent signals with durations as short as 3.57µs (with 100% POI), which is the best POI currently available. The PXA also offers a noise floor of -157 dBm/Hz at 10GHz with no preamp, which according to Agilent, that this is the lowest noise floor available.

So what is real time? "With this product, acquisition and processing is gap-free, so finding intermittent issues or analysing dynamic signals becomes much easier," says Overdorf. "FPGAs provide parallel processing so there are non-task interruptions. Without real-time capabilities like the ones in this PXA, engineers would need to spend more time analysing data to indentify and understand elusive signals."

The new PXA is designed to scan wide spans of spectrum, with 160MHz real-time bandwidth and up to 50GHz frequency range. In order to enable detection of small signals, the product has up to 75 dB spurious-free dynamic range across the 160MHz bandwidth.

The real-time PXA uses ASICs and FPGAs to convert sampled signal data into signal spectra at nearly 300,000 spectra per second. Spectrum data is combined to create information-rich displays such as density (histograms). Alternatively, the stream of spectra can used to produce a spectrum-specific and behaviour-specific frequency-mask trigger (FMT).

Overdorf cites a use case where there is an intermittent issue. "Engineers simply plug into this new RTSA capability and see the problem," he says, "In the past, they would need to use a dedicated real-time analyser that cost on the order of $100,000." With the Agilent product, engineers can use the current PXA spectrum analyser hardware and, through a firmware upgrade, have the real-time capability.

Particularly well suited for applications such as radar, electronic warfare and military communications, the RTSA is available as two upgrade options for new and existing PXA signal analysers. Both options are available now worldwide. List prices are as follows:

• N9030AK-RT1 real-time spectrum analyser up to 85MHz bandwidth: $7,224.
• N9030AK-RT2 real-time spectrum analyser up to 160MHz bandwidth: $10,320.

The starting price for a new N9030A PXA signal analyser with the real-time spectrum analyser option up to 160MHz bandwidth is $96,304.

More information is available at www.agilent.com/find/real-timePXA.

- Janine Love
  EDN