Hi morse micro,
We are in the process of optimizing the antenna matching for FGH100MABMD module (based on the mm6108). Is it possible to put the module into a constant transmission mode where it is either repeatedly transmitting a large packet or a monotone frequency so that we can view it on the spectrum analyzer and measure the output RF power using a spectrum analyzer?
Hi doludiran,
We recommend antenna tuning with a Vector Network Analyzer. You can potentially optimize for your TX power with a spectrum analyzer (depending on the approach), but you’re missing out on the data for both the EVM and EMC of your transmission, so you’d be missing the ability to balance the TX power with the signal distortion in a way that won’t fail compliance testing. When we optimize antennas, we keep the modules/chip off the board and attach a VNA with a pig tail.
On your questions, we don’t make our RF test suite publicly available, however access can be requested by emailing support@morsemicro.com with the same account/address that you’ve used to register for our customer portal (make an account if you haven’t done so). Large continuous streams of packets does seem like it’d be covered by something like an IPerf.
Hi Michael,
What about intermods…?
Hey Dean,
Our chips (and HaLow in general) use wideband modulated waveforms rather than a small number of discrete tones. Those intermods found in narrowband systems show up instead as spectral regrowth or degradation of modulation quality.
We’ve designed for the standard 50 Ω load impedance, so tuning your antenna to that target gives you the optimal performance (with regards to the trade-off between output power, EVM, SNR for Rx, and EMC compliance). You can validate this using normal modulated signals, the classic two-tone intermodulation behavior isn’t necessarry as the relevant distortion mechanisms are reflected in the EVM and spectral emissions measurements.