R&S TSMW-K1
Introduction
System Requirements
User Manual 1503.3776.32 - 08
10
1.2.1
Additional Requirements for I/Q Streaming over LAN
Use of the R&S TSMW feature "I/Q streaming" places additional requirements on the
computer equipment used. The following items are essential:
● PCI-Express Gigabit Ethernet Adapter
● High-speed hard disk with >40MB/s sustained transfer rate (write) - for calculating
the actual disc speed required, see the equation below.
These requirements are due to the large amount of data created during I/Q streaming.
Based on the above facts it is useful to calculate the I/Q data rate and to define the
minimum system requirements for the computer equipment.
1.2.1.1
Formula
[Bitrate TSMW] = [Sample rate in MS/s]*2*(X + Y)*Z*OVal
X
Number of selected channels on RF 1.
Y
Number of selected channels on RF 2.
Z
Number of bits used for the data transfer. Possible values are 8 Bit, 12 Bit, 16 Bit and 20 Bit.
OVAL
Overhead value, approximately 1,1.
1.2.1.2
Example I/Q Streaming
The following parameters are used for an I/Q raw-data streaming measurement with a
R&S TSMW via Gigabit LAN interface:
X = 1
On RF1 two sub channels are selected.
Y = 2
On RF2 four sub channels are selected.
Z = 20 Bit
Data transfer format is 20 Bit.
OVAL = 1,1
Overhead value 10%.
Sample rate
= 3[MS/s]
Sample rate 3 [MS/s]
Estimated data transfer rate:
3000000 Samples/s * 2 * (1 + 2) * 20 Bit/Samples * 1,1
= 396000000 Bit/s
= 49,5 MByte/s
This means that 49,5 MB per second has to be transferred from the R&S TSMW to the
computer over a Gigabit Ethernet card (and saved on the hard disk) during this I/Q
data streaming measurement.