How to design demoule model RF-Front end

Dear All :

I have some question about dual-mode RF-Fronet end . One is 1.4G~1.67G ,
another is 480M~880M . I think I need do two LNA and mixer . But I about the Board system design, Do I need two antenna ? Or can I use on antenna ? How to do that , Thanks

Yes, you can use only one dual band antenna. You need a filter in front of your LNA.

You have several solutions here you one:
one antenna, two filters, two LNA's , two power detectors, two amplifiers with AGC and two mixers.Be care in impedance matching between antenna and filters you need impedance transformer for matching on antenna impedance.
Also ther are and combination with swithes, diplexers, dividers, oscillators in depend what you want.

Antenna type can be some dual band patch, for example inverted F.