Our customer is using Evaluation Kit of HMC6000 and HMC6001, and he has some questions about the GUI.
(1) Is "BB LF Corner" control on the GUI for HMC6001 corresponding to ROW3<4:5>? If yes, the GUI doesn't match to datasheet. Which is correct? If no, what function is "BB LF Corner" for?
(2)Could you please advise me about a function of "VCO Amp Bias" on the GUI for HMC6000? Or which ROW is corresponding to "VCO Amp Bias"? And the customer would like to adjust VCO for improving the phase noise. How should we do for improving the phase noise?
(3)The customer has beed testing of this Eva. kit by MSC-10 (SC 16QAM). However the EVM was 13.413%. What should we check for improving the EVM?
The BB Lowpass Corner on the GUI controls the lowpass corner on the baseband amplifiers. This is set by using ROW3<6:7>.
The VCO has already been optimized for the best phase noise. Changing the VCO BIAS AMP setting will only degrade the performance. The replacement parts (HMC6300/6301) have an improved synthesizer that will support 64QAM. The new devices also have a feature that allows for an external external LO for support up to 256QAM.
13.4% EVM is approximately 18dB SNDR. Typically about 20dB SNDR is required for 16QAM but will vary depending on the modem. There are A LOT of variables to this measurement:
- Is the TX optimized
- Is the RX carrier level within an acceptable range
- Is the RX gain optimized
- Is multipath involved
Thank you for your answer.
Thanks & Regards,