How does reflex receiver provide more gain bandwidth product?

[iVenky]

I am really confused with the reflex receiver that I read in Thomas Lee's RF book where he discusses about it. He says it provides more Gain Bandwidth product than that of the amplifier that is inside the system. Here's one link from the stanford site (judging from the link's name).

http://www-smirc.stanford.edu/papers/chapter1.pdf

In that search for reflex circuit and read that where he says it provides more gain bandwidth product which I just couldn't understand.

Thanks a lot

 

[betwixt]

A reflex receiver achieves higher gain by employing components to keep the RF and AF apart from each other. The same amplifier first passes RF, it is then recified (detected) then fed back through the amplifier again a second time. By providing different paths for the RF and AF, it can amplify both at the same time and hence provide higher than normal gain. You can think of it as being a wideband amplifier which has within it a high pass and a low pass filter. The detector stage removes the modulation from the signal arriving through the high pass filter and recovers the low frequency modulation from it. The demodulated audio is then sent back through the same amplifier via the low pass filter.

Brian.