Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
That is a strange circuit!
I can't tell what is supposed to do, maybe an FM transmitter, maybe a direct conversion receiver, regardless, the component values are odd and as it can't consume more than 1.2uA I wouldn't worry about efficiency.
I've no idea why two transistors are used, why a 1W resistor is needed or what the two incorrectly drawn diodes are for.
It's a "Base Grounded Colpitts" Oscillator ,nothing special.
The purpose of using two transistors may be to increase the Collector Current in order to obtain more power OR to satisfy the Oscillation Conditions. It ought be well examined.
But using this configuration IMHO has no sense because it will also increase the Noise.
The main principle is to design a Silent Oscillator even at low power then amplify this obtained signal in a appropriate way.