Multiple access

What does Frequency Division Duplexing (FDD) provide for every user?

• No frequency allocation

• A single frequency band for transmission

• Two distinct bands of frequencies

• One frequency band for both uplink and downlink

In Time Division Duplexing (TDD), how are the transmission directions managed?

• By using a single time slot for both directions

• By alternating time slots

• Using two distinct frequency bands

• By employing frequency hopping

What is the maximum vulnerable period in pure Aloha systems?

• One slot time

• Three slot times

• Four slot times

• Two slot times

What is a key feature of FDMA systems?

• Time slots are dynamically assigned

• Each user is allocated a unique frequency band

• Users share the same frequency band

• All users can transmit simultaneously

What does TDMA stand for?

• Time Division Multiple Access

• Time Division Management Access

• Time Division Modulation Access

• Time Domain Multiple Access

Which of the following is a characteristic of CDMA?

• Operates only in narrowband systems

• Requires guard slots between users

• Uses spreading codes for transmission

• Requires fixed frequency bands

What is the main advantage of using spread spectrum techniques?

• Lower power consumption

• Robustness against jamming

• Simpler hardware requirements

• Higher bandwidth efficiency

In Frequency Hopped Multiple Access (FHMA), what is varied in a pseudo-random fashion?

• The transmission power

• The carrier frequency

• The modulation technique

• The data rate

What is the purpose of guard slots in TDMA systems?

• To allow for dynamic slot assignment

• To avoid interference between users

• To reduce power consumption

• To increase data rates

What does the term 'soft capacity' refer to in CDMA systems?

• Strict frequency management

• Fixed number of users per channel

• High power requirements

• Ability to accommodate varying numbers of users