The LTE uplink scheduler is located at the base station in LTE. The minimum transmission unit of LTE scheduler is known as a resource block. The radio resource that is available in the uplink LTE system is defined in both frequency and time domains. In the frequency domain, each RB consists of 12 consecutive subcarriers and in the time domain it is made up of one time slot of 0.5ms duration. Each 1ms Transmission Time Interval (TTI) consists of 2 slots, and a subframe is defined as 10 TTIs. At each TTI, multiple RBs can be assigned to a number of users with different classes; each resource block however can be assigned to at most one user. The LTE scheduler has MHz bandwidth, divided into RBs. Table 3.1 shows the channel bandwidth for a given quantity of resource blocks. We assume that the scheduler is capable of assigning RBs arbitrarily to all users and each RB has a bandwidth of. Let denotes the RB index set. For simplicity, we suppose that uniform power allocation across all subcarrier. Table 3.1 Number of resource blocks for different LTE bandwidths Channel 1.4 3 5 10 15 20 bandwidth [MHz] Number of resource 6 15 25 50 75 100 blocks Figure 3.2 3GPP LTE radio frame structure We define a variable to indicate the number of resource blocks assigned to traffic flows. According to Shannon-Hartley theory, for uplink direction, the maximum uplink channel throughput of class-c in the SC-FDMA multiplex can be expressed as [34] [35]: (3.2)
The LTE uplink scheduler is located at the base station in LTE. The minimum transmission unit of LTE scheduler is known as a resource block. The radio resource that is available in the uplink LTE system is defined in both frequency and time domains. In the frequency domain, each RB consists of 12 consecutive subcarriers and in the time domain it is made up of one time slot of 0.5ms duration. Each 1ms Transmission Time Interval (TTI) consists of 2 slots, and a subframe is defined as 10 TTIs. At each TTI, multiple RBs can be assigned to a number of users with different classes; each resource block however can be assigned to at most one user. The LTE scheduler has MHz bandwidth, divided into RBs. Table 3.1 shows the channel bandwidth for a given quantity of resource blocks. We assume that the scheduler is capable of assigning RBs arbitrarily to all users and each RB has a bandwidth of. Let denotes the RB index set. For simplicity, we suppose that uniform power allocation across all subcarrier. Table 3.1 Number of resource blocks for different LTE bandwidths Channel bandwidth [MHz] 1.4 3 5 10 15 20 Number of resource blocks 6 15 25 50 75 100 Figure 3.2 3GPP LTE radio frame structure We define a variable to indicate the number of resource blocks assigned to traffic flows. According to Shannon-Hartley theory, for uplink direction, the maximum uplink channel throughput of class-c in the SC-FDMA multiplex can be expressed as [34] [35]: (3.2)
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