Mobile realtime I/Q streaming

Your task

To keep pace with the development of new standards or components, you want to record any type of RF signal in the baseband to further process or analyze such signals. Or you want to measure an unknown signal that you want to record together with geographical information for analysis at a later time.

The R&S®TSMW radio network analyzer with the R&S®TSMW-K1 option is the ideal tool for performing the above and multiple other tasks.

T & M solution

The R&S®TSMW-K1 option for the R&S®TSMW enables users to perform I/Q baseband measurements directly from MATLAB® or a user-specific C++ application and to post-process the measurement data as required. In MATLAB®, signal processing algorithms can be developed based on a generic C++ API and converted into a powerful C++ application with minimum effort.

The R&S®TSMW includes a variety of features:

• Two frontends with a 20 MHz bandwidth to h andle center frequencies from 30 MHz to 6 GHz for independent or simultaneous measurements
• Sampling rate reduction with user-specifi c fi ltering to implement any sampling rate from 1 Msymbol/s to 21.94 Msymbol/s
• Channel splitting into up to four subchannels per channel
• Integrated preselection with preamplifi er for a high dynamic range also in the presence of strong interferers
• Automatic attenuation control
• Integrated GPS

A special highlight offered by the R&S®TSMW is seamless I/Q streaming with a bandwidth of up to 20 MHz. I/Q data can either be automatically stored on the hard disk of the control PC or processed online (provided that the computing power is sufficient). Here, the R&S®TSMW can be used as a mobile I/Q recorder and the integrated GPS allows the assignment of I/Q measurement data and geographical position.

The maximum recording time depends on the selected sampling rate and bit width. Approx. 37 Mbyte/s of data is obtained for a bandwidth of 10 MHz (≙ 11 Msymbol/s and 12-bit resolution), for example. In this case, a fast 500 Gbyte hard disk allows a recording time of >200 minutes.

An extra feature of the MATLAB® streaming application allows parts of the recorded I/Q stream to be converted into the Rohde & Schwarz I/Q format and thus to be output on Rohde & Schwarz signal generators. The R&S®TSMW is rugged and compact. Its flexible DC power supply makes it ideal for mobile scenarios.

Application

The supplied MATLAB® example application (see figure) enables users to immediately put the R&S®TSMW into operation. After defining all important parameters such as center frequency, digitization resolution and measurement bandwidth, users can start I/Q baseband measurements both in the block and streaming mode. In addition, measurement data can be exported to the MATLAB® workspace for further analysis, which already allows simple measurement tasks to be solved.

The supplied MATLAB® example application is provided in the source code. Users can easily see and comprehend how the application was implemented in MATLAB® or make program-specific expansions or adaptations to handle specific applications. Moreover, C++ example applications are offered to enable easy porting of algorithms from MATLAB® to C++. A detailed manual is provided to support developers.

For the first time, the R&S®TSMW-K1 option enables users of the mobile radio network analyzers from Rohde & Schwarz to perform I/Q baseband measurements in the field in addition to optimizing mobile radio networks. Offering unrivaled sensitivity and flexibility, the R&S®TSMW is clearly superior to other instruments in its class.

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