Capacity Evaluation for IEEE 802.16e Mobile WiMAX

Table 1

OFDMA parameters for Mobile WiMAX [3, 8, 9].

Parameters	Values
System bandwidth (MHz)	1.25	5	10	20	3.5	7	8.75
Sampling factor	28/25				8/7
Sampling frequency ($F_s$,  MHz)	1.4	5.6	11.2	22.4	4	8	10
Sample time ($1/F_s$, nsec)	714	178	89	44	250	125	100
FFT size ($N_{\text{FFT}}$)	128	512	1,024	2,048	512	1,024	1,024
Subcarrier spacing ($\mathrm{\Delta }f$, kHz)	10.93				7.81		9.76
Useful symbol time ($T_b=1/\mathrm{\Delta }f\text{,}$$\mu \text{s}$)	91.4				128		102.4
Guard time ($T_g=T_b/8\text{,}$$\mu \text{s}$)	11.4				16		12.8
OFDMA symbol time ($T_s=T_b+T_g\text{,}$$\mu \text{s}$)	102.8				144		115.2