Paper Info
Title
Differential amplify-and-forward cooperative relaying in a software-defined radio testbed with an aerial relay node.
Abstract
In this work, we implement and demonstrate differential amplify-and-forward (DAF) cooperative relaying as a novel diversity technique to combat bit errors and outages common in airborne environments. By using differential modulation and demodulation, we reduce the system complexity by avoiding channel estimation which is often unreliable or computationally costly in dynamic environments with mobile nodes. We further simplify the requirements of the relay node by employing amplify-and-forward relaying where the relay amplifies the incoming signal and retransmits at a different frequency assignment. We implemented DAF relaying using the GNU Radio software platform and Universal Software Radio Peripherals (USRPs). We designed a pilot sequence specifically for differential modulation and implemented frame level synchronization which can combine frames properly at the destination node for joint decoding even when some frames are dropped either from the direct link or relay link We verified simulation results of DAF relaying in a controlled test in an anechoic chamber and showed that cooperative relaying achieves significantly lower bit error rate compared to direct link transmission and two-hop relaying schemes. We then validated our system outdoors with an airborne relay node and demonstrated our results.
Year
Venue
Field
2017
IEEE Military Communications Conference
Demodulation,Synchronization,Software-defined radio,Computer science,Communication channel,Computer network,Frequency assignment,Decoding methods,Computer hardware,Relay,Bit error rate
DocType
ISSN
Citations 
Conference
2155-7578
0
PageRank 
References 
Authors
0.34
7
4
Name
Order
Citations
PageRank
Ngwe Thawdar172.73
Ulysses Lee201.01
Weifeng Su31612102.93
Dimitris Pados420826.49