Wireless Communication in Biomedical IoT devices

Impulse radio ultra wideband(IR-UWB) architectures are adopted for the implementation of duty cycled radios 

They demonstrate excellant energy efficiency for high data rate applications however the energy efficiency is not equally Perfect for low data rate applications.

In low data rate applications the power leakage is much higher and can even degrade the energy efficiency at 100kbps data rate.

The IR-UWB transmitter does not require any mixer or phase lock loop,which minimises the power consumption of the system.

For wireless transmission of the data on-off keying(OOK) based transmitter scheme -  in which bit 1 is represented by a short pulse and bit 0 is represented by the absence of a pulse signal needs to be analysed to reduce the complexity of the transmitter architecture.

The above system level block diagram of the IR-UWB transmitter which is designed using a standard180nm complementary metal oxide semiconductor(CMOS)  includes

An impulse generator designed with digital gates

Its core building blocks are

1.Tunable delay block

2. An inverter

3. A NAND logic gate

4. Another inverter to generate the desired signal

Below block diagram puts all these blocks together

A tunable cross coupled inductor-capacitor based LC oscillator for uoconverting the baseband impulse signal to UWB frequency range.

A buffer to drive the 50ohm antenna.