This paper presents mmCPTP, a cross-layer end-toend protocol for fast delivery of data over mmWave channels associated with emerging 5G services. Recent measurement studies of mmWave channels in urban micro cellular deployments show considerable fluctuation in received signal strength along with intermittent outages resulting from user mobility. This results in significant impairment of end-to-end data transfer throughput when regular TCP is used to transport data over such mmWave channels. To address this issue, we propose mmCPTP, a novel cross-layer end-to-end data transfer protocol that sets up a transport plug-in at or near the base station and uses feedback from the lower layer (RLC/MAC) to opportunistically pull data at the mobile client without the slow start and probing delays associated with TCP. The system model and end-to-end protocol architecture are described and compared with TCP and IndirectTCP (I-TCP) in terms of achievable data rate. The proposed mmCPTP protocol is evaluated using NS3 simulation for 5G NR (New Radio) considering a high-speed mobile user scenario. The system is further validated using a proof-of-concept prototype which emulates the high-speed mmWave/NR access link with traffic shaping over Gbps ethernet. Results show significant performance gains for mmCPTP over TCP and I-TCP (2.5x to 17.2x, depending on the version).
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Cognitive Overlay for Inter-system Cellular Dynamic Spectrum Sharing in the Downlink
This paper assesses the feasibility of a novel dynamic spectrum sharing approach for a cellular downlink based on cognitive overlay to allow non-orthogonal cellular transmissions
from a primary and a secondary radio access technology concurrently on the same radio resources. The 2-user Gaussian cognitive interference channel is used to model a downlink scenario in which the primary and secondary base stations are co-located. A system architecture is defined that addresses practical challenges associated with cognitive overlay, in particular the noncausal knowledge of the primary user message at the cognitive transmitter. A cognitive overlay scheme is applied that combines superposition coding with dirty paper coding, and a primary user protection criterion is derived that is specific to a scenario in which the primary system is 4G while the secondary system is 5G. Simulation is used to evaluate the achievable signal-to-interference-plus-noise ratio (SINR) at the 4G and 5G receivers, as well as the cognitive power allocation parameter as a function of distance. Results suggest that the cognitive overlay scheme is feasible when the distance to the 5G receiver is relatively small, even when a large majority of the secondary user transmit power is allocated to protecting the primary user transmission. Achievable link distances for the 5G receiver are on the order of hundreds of meters for an urban macrocell or a few kilometers for a rural macrocell.
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- Award ID(s):
- 2034616
- NSF-PAR ID:
- 10293939
- Date Published:
- Journal Name:
- IEEE International Conference on Communications workshops
- ISSN:
- 2694-2941
- Page Range / eLocation ID:
- 1-6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
