Language Reference
MDS
Description The MDS command determines if binary data is transmitted as one byte or one word (two
signicant digits contained in the binary data. Use MDS to improve speed and economize on storage space in memory. Better throughput (speed) is achieved with MDS B, at the sacrice of resolution and thus accuracy. During normal operation, trace data is provided in decimal form. Use MDS when the TDF command species trace data as binary data. MDS also determines the format of data the spectrum analyzer receives from the computer. MDS B multiplies each byte of data received by 2 raised to the power of the scaling factor.
MDS B divides each byte of data sent by 2 raised to the power of the scaling factor. In the example below, the number 16 is processed with a scaling factor of 3. (Number 16 represents the amplitude of a trace data point.)
Input Data | Output Data |
0001 0000 2 23 = 1000 0000 | 0001 0000 4 23 = 0000 0010 |
A scaling factor of 8 provides adequate resolution for most measurement applications. When a scaling factor of 8 is used, trace data from 0 to 255 is sent as 0. Trace data from 256 to 511 is sent as 1 (0000 0001). Trace data from 512 to 767 is sent as 2 (0000 0010), and so on.
If the trace is in linear units, the range is 0 to 10,000. For linear mode, a scaling factor of 6 is more appropriate (returning values from 0 to 156 for trace data).
In standard 10 dB log mode, values range from 032,768 to +32,767. A scaling factor of 8 oers coverage of the full range (measurement units are hundredths of a dB). However, if it is known that the signal will not exceed 6156 dB, a scaling factor of 7 is more appropriate. The scaling factor of 7 preserves more resolution and accuracy. For a scaling factor of 7 in log mode, the minimum resolution is 1.28 dB. A scaling factor of 8 provides 2.56 dB resolution.