Multiplexing Techniques

Access Technique

Technique Number of users 4

Resource Parameters

Total bandwidth 8 MHz Guard interval 10% SNR (dB) 20

Metrics

Spectral efficiency-

Guard overhead-

Per-user BW-

Multiple Access
TDMA: users share time, each gets full BW in a slot.
FDMA: users share frequency, each gets a sub-band.
CDMA: users share code (spread spectrum), all overlap in time & frequency.
OFDMA: users share subcarriers (LTE/5G resource blocks).

Guard intervals prevent inter-slot/inter-band interference but reduce efficiency:
η = (N × slot) / (N × slot + (N-1) × guard)