  This survey paper provides a detailed explanation of Long Term Evolution
cellular network packet scheduling algorithms in both downlink and uplink
directions. It starts by explaining the difference between Orthogonal Frequency
Division Multiple Access that is used in downlink transmission, and Single
Carrier Frequency Division Multiple Access is used in uplink. Then, it explains
the difference between the LTE scheduling process in the donwlink and uplink
through explaining the interaction between users and the scheduler. Then, it
explains the most commonly used downlink and uplink scheduling algorithms
through analyzing their formulas, characteristics, most suitable conditions for
them to work in, and the main differences among them. This explanation covers
the Max Carrier-to-Interference, Round Robin, Proportional Fair, Earliest
Deadline First, Modified EDF-PF, Modified-Largest Weighted Delay First,
Exponential Proportional Fairness, Token Queues Mechanism, Packet Loss Ratio,
Quality Guaranteed, Opportunistic Packet Loss Fair, Low Complexity, LC-Delay,
PF-Delay, Maximum Throughput, First Maximum Expansion, and Adaptive Resource
Allocation Based Packet Scheduling. Lastly, it provides some concluding
remarks.
