Waveform recording firmware gains advanced gating

Edited by the Electronicstalk editorial team Aug 16, 2004

The latest SSR firmware for Acqiris' AP240 and AP235 dual-channel reconfigurable analyser platforms offers new "data gating" functions that further maximise event transfer rate.

Acqiris has added new functionality to its Sustained Sequential Recording (SSR) firmware, which enhances the ability to acquire, store and transfer sequential waveforms to a host PC at high sustained trigger rates, increasing measurement throughput.

The latest version of the SSR firmware for Acqiris' AP240 and AP235 dual-channel reconfigurable analyser platforms offers new "data gating" functions that further maximise event transfer rate and that now allow the setting of pre- and post-markers to predefined threshold gates.

Capable of digitising and storing waveforms at sampling rates up to 2Gsample/s with the AP240 and 1Gsample/s with the AP235, the analyser cards are ideal for applications where fast sequential or burst-style repetitive signals (or pulses) are acquired and recorded, such as in signal intelligence (SIGINT) and synthetic aperture radar (SAR).

In addition, the new SSR firmware "data gating" functions enable the user to precisely and exclusively record responses that exceed precise amplitudes, or that occur over specific times of interest, making the AP240 and AP235 extremely well suited for ultrasound, radar, lidar or other time-of-flight measurement applications.

Using SSR firmware, waveforms digitised, by the AP240 or AP235 at 1Gsample/s for 1us, in sequences of 1000 segments per memory bank, can be continuously acquired and transferred to a PC at sustained rates up to 100,000 times per second (50,000 if sampling at 2Gsample/s).

The onboard DPU stores digitised waveforms in a "ping-pong" fashion in a dual-bank memory system, such that one memory bank is used to store a waveform, or sequence of waveforms, while the other memory bank is being read out over the analyser cards' fast PCIbus at rates of up to 100Mbyte/s.

Once one memory bank has been filled with digitised data, an automatic switch directs data to the second bank.

The combination of rapid automatic switching between banks and state-of-the-art trigger circuitry substantially reduces dead time between successive acquisitions, and also enables the sequential waveform recording at high sustained trigger rates.

The firmware's smart "data gating" further maximises the event transfer rate, performing easy and effective data reduction, and rejecting unwanted information, while enhancing the maximum trigger rate.

On readout, the user can select "predefined gates" to transfer data points within a user-defined timing range, or "threshold-defined gates" to transfer data points above or below a user-defined threshold.

The latest version of the SSR firmware now includes the ability to gather pre- and post-threshold data around these gates, so up to 16 samples before the first threshold marker, and up to 16 samples after the second threshold marker can be stored for eventual analysis.

The SSR firmware enables sequential acquisition and recording in "burst mode", with trigger rates within the burst of up to 500kHz for sequences of 1us-long waveforms digitised at 1Gsample/s sample rate.

Taking advantage of the platforms' long processing memory option (AP240-P24MB, AP235-P24MB), up to 8191 segments of 1024 points each can be acquired in a single burst on each memory bank.

The firmware is also able to handle continuous acquisition, and transfer digitised data to the host PC at 100Msample/s sample rate with 99.995% live time in the single-segment acquisition mode.

Both the AP240 and AP235 analyser platforms have dual-channel capability.

Each channel has full front-end signal conditioning with calibrated gain and offset ranges, an independent digitiser, and a separate FPGA-based DPU.

The Model AP240 represents the top of the range with 1GHz front-end bandwidth, 1Gsample/s ADCs, and up to 12Mbyte of memory per channel (48Mbyte optional).

The AP235 uses a similar architecture as the AP240 but offers a more economical package for lower frequency applications.

The unit's front-end bandwidth is 500MHz and the maximum sampling rate is 500Msample/s.

For single-channel applications both cards can use their two channels, doubling the maximum sampling rate (2Gsample/s for the AP240 and 1Gsample/s for the AP235 on either input, software selectable) and overall timing resolution.

Pricing for an AP240/235 with enhanced SSR firmware starts at $10,980.

Delivery is 6 weeks ARO.