Analysis of MIPI RFFE interfaces with option for R&S RTO scopes

September 28, 2014 // By Graham Prophet
To control the RF frontend, state-of-the-art smartphones use the serial RFFE bus standardised by the MIPI Alliance. The RTO-K40 option for RTO oscilloscopes from Rohde & Schwarz addresses the need for fast analysis and testing of MIPI RFFE interfaces. The option also offers automatic glitch rejection, which is claimed to be unique.

The R&S RTO-K40 MIPI RFFE serial triggering and decoding option from Rohde & Schwarz is a solution that enables developers of RF frontends and modules with RF frontend (RFFE) control interface to verify and debug designs and put these components into operation. The RTO oscilloscope with its high acquisition rates and minimal blind times is able to trigger on MIPI RFFE-specific protocol data. The decoded protocol content is displayed in an easy-to-read format.

The RTO-K40 option allows users to directly trigger on content such as "extended register write" or error states such as "bus park error" of the MIPI RFFE protocol. This option is claimed to be the only tool on the market that supports automatic rejection of glitches during decoding as specified in the standard. The decoded protocol content is displayed in a colour-coded overview as well as in tabular format.

The search and navigation function helps users to keep track of long records and to directly jump to positions of interest in the protocol. As a result, users can easily isolate states, quickly identify design bugs and time-correlate decoded RFFE commands with other signals in the circuit under test. The R&S RTO oscilloscope allows parallel decoding of up to four different serial protocols so that any interactions between modules can be immediately detected. The MIPI RFFE interface can be connected to both the analogue and digital channels of the oscilloscope.

The MIPI RFFE interface has been specified by the Mobile Industry Processor Interface (MIPI®) Alliance for controlling components of the RF frontend such as output amplifiers, filters, power regulation modules and sensors.

Rohde & Schwarz;