The PXB does not directly support a separate file header.
The PXB supports three specific file types:
Signal Studio encrypted or securewave files. When waveforms are created using Signal Studio applications, the header, marker, and I/Q data are encrypted within the generated waveform file (.wfm). Every waveform, regardless of file name or extension, is read to see if it matches the encrypted file format. If it does not, it is treated as binary data.
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The PXB does not directly support a separate file header. |
Binary waveform files. The PXB accepts data in the form of bytes. The I/Q file contains the interleaved I and Q data points (signed 16-bit integers for each I and Q data point). Each I/Q point equals one waveform point.
2-byte integer values
Input data range of −32768 to 32767
Minimum of 256 samples per waveform (256 I and 256 Q data points)
Interleaved I and Q data
Big Endian byte order
Marker files use one byte per I/Q waveform point to set the state of the markers either on (1) or off (0) for each I/Q point. When a marker is active (on), it provides an output trigger signal to the baseband generator block. Because markers are set at each waveform point, the marker file contains the same number of bytes as there are waveform points. For example, for 200 waveform points, the marker file contains 200 bytes.
You can download or extract waveform data created in any of the following ways. Prior to creating and downloading files, you need to take into consideration the file size and the amount of remaining PXB memory.
with Agilent Signal Studio software using SCPI commands or any standard Windows networking method, such as a mapped network drive. Files do not have to reside on the hard drive to be selected for downloading to baseband memory. You can also copy compatible licensed encrypted data files from an external media. Arb waveform encryption of proprietary information is supported on the external non-volatile USB flash memory.
with signal simulation software, such as MATLAB or using advanced programming languages, such as C++, VB or VEE. Refer to Create and Download Waveform Data using Advanced Programming Languages for sample code algorithms and syntax.
The PXB allocates waveform playback memory or volatile memory in blocks of 32 bytes (8 samples, 4 bytes per sample) with a maximum of 512 MSamples for each DSP unit on the baseband board. For example, a waveform file with 256 samples (the minimum number of samples) has 1024 bytes (4 bytes per sample x 256 samples), and the PXB allocates 1024 bytes of memory.
Playback memory does not survive cycling of the PXB power. To play back waveforms after cycling the PXB power, you must load waveforms from non-volatile waveform memory (NVWFM) to volatile waveform memory.
Storage memory refers to non-volatile memory where files survive cycling the PXB power. Files remain until overwritten or deleted. Files can be stored on the internal PXB disk drive, to an external USB memory device. The amount of available non-volatile memory varies by the size of the other files that share the USB flash or hard drive memory.