I’'m having trouble finding the right (and small, patch or fractal) antenna+compensation to use for dual-band usage of the WS6318 module.
The technical specifications of the WS6318 states that the maximum allowed VSWR is 1.5:1. However that is stated for the minimum voltage (of 3.2V) as a side-note.
I’m using the 6318 because of size constraints. Therefore I would also need a small antenna. However, every antenna I have found so far has a VSWR < 3. It would need compensation. But I’m using both frequency bands and compensating for both bands on one antenna proves rather difficult. Besides, after opening up various other GSM-based products I’ve found that they hardly use compensation or use a single compensation network for both bands.
- How would I go at this? Design a single compensation network? Or split up the frequency bands through various networks and (possibly) multiple antenna’s?
- What is the actual, full supply-range allowed VSWR?
- How would the module respond if I directly connect a VSWR < 3 patch antenna? Would the module be damaged?
- How would one compensate for both the 900 and 1800 bands? Multiplex? Single network?
What did you do?
Thank you in advance,