Imec and Holst Centre achieve breakthrough in battery-less radios
At today’s International Solid State Circuit Conference, imec and Holst Centre report a 2.4GHz/915MHz wake-up receiver which consumes only 51µW power. This record low power achievement opens the door to battery-less or energy-harvesting based radios for a wide range of applications including long-range RFID and wireless sensor nodes for logistics, smart buildings, healthcare etc.Toda
Imec and Holst Centre developed an innovative radio architecture based on double sampling to overcome the 1/f noise problem. This noise affects most low data rate (10-100kbps) radios. As a consequence, these radios traditionally have a higher power budget than higher data rate radios achieving the same performance. By using a double-sampling technique the offset and 1/f noise is reduced and consequently the sensitivity of the receiver improves proportionally as data-rate scales.
The wake-up receiver chip was implemented in a 90nm digital CMOS technology and occupies an area of 0.36mm2. Measurements on silicon show a sensitivity of -75dBm (SNR>12dB) for the 915MHz receiver at 100kbps OOK (on off keying) modulation. When scaling the data rate to 10kbps and filtering the out-of-band noise, the sensitivity is improved by 5dB. For the 2.4GHz receiver, the sensitivity is -64dBm and -69dBm for 100kbps and 10kbps data rate respectively.
“Within our wireless autonomous sensor system research, we aim to develop wireless sensor systems powered by energy harvested from the environment instead of using batteries. The power budget of such systems is only 100µW for the DSP, radio and sensor. This ultra-low power radio of only 51µW with small form factor is a major step forward to achieve our goal. It opens the door to many new battery-less applications such as long-range RFID, smart lighting, and sensor tags.” said Bert Gyselinckx, general manager imec the Netherlands at Holst Centre.
At this week’s International Solid State Circuit Conference, imec and Holst Centre present their newest breakthroughs in ultra-low power design for wireless communications and wireless sensor networks and in organic electronics with an impressive number of contributions including 10 reviewed publications and 6 contributions to tutorials and workshops.
This news release is based on paper 11.5: A 2.4GHz/915MHz 51μW Wake-Up Receiver with Offset and Noise Suppression.