Make Cellular Internet of Things Receivers Smart
Recent developments in the 3GPP standard organization produced cellular standards for the Internet of Things (IoT). It is forecast that by the end of the decade billions IoT devices will be connected to the Internet, many in remote or poorly covered spaces such as rural areas and basements. The 3GPP produced two standards for the cellular IoT with extended coverage support: 4G based NB-IoT and a 2G based Extended Coverage GSM for IoT (EC-GSM-IoT). The latter promises up to 20 dB coverage increase compared to legacy solutions. Current research at the institute produced a first prototype of an EC-GSM-IoT modem as an extension to the stoneEDGE project. The extended coverage is achieved by blindly repeating data packets up to 16 times. The terminal attempts to combine the blind repetitions before attempting to decode. There exist a number of combining schemes ranging from I/Q-, prefilter-, equalizer-, Chase-, and decoder-combining. However, not every combining scheme is equally well suited for arbitrary radio channel conditions.
In this project, the suitability of selected combining schemes under various radio channel conditions, such as AWGN and slow and fast fading LTV channels, shall be studied. Then, methods and algorithms to estimate the channel coherence time shall be developed. The estimated channel coherence time can then be used to optimally choose the best combining scheme for the observed channel conditions. The chosen algorithmic candidate can then be implemented in HDL and incorporated into the stoneEDGE project, which already includes signal conditioning, equalization, and channel decoding. The result can then be tested on a Kintex FPGA board with a PULP CPU in conjunction with an evalEDGE FMC module as analog front-end. ASIC synthesis is also an option. This project is a perfect opportunity to solve a hot topic algorithmic problem and make cellular IoT receivers smart.
- Looking for interested students (Semester or Master Thesis)
- Contact: Benjamin Weber
- Interest in mobile communication
- 25% Theory
- 25% Algorithm Design
- 25% Implementation
- 25% Testing
 3GPP. Release 13. http://www.3gpp.org/release-13, 2016.