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QUESTION: An unguided signal can be split into several transmission paths, with each path experiencing different impediments (e.g., reflection, scattering, etc.), thus causing each path to vary in length. This results in several copies of the signal reaching the receive at slightly different times, thus leading to signal distortion. This is termed multipath fading.

True False

QUESTION : MIMO antenna systems intentionally takes advantage of multipath using spatially diversified transmit and receive antennas, and digital signal processors (DSPs).

True

False

QUESTION: Select the correct statement(s) regarding Code Division Multiple Access (CDMA).

		a. in a CDMA link, multiple users separated by unique PN codes, share the entire operating frequency bandwidth
		b. CDMA is a direct sequence spread spectrum (DSSS) technique
		c. CDMA links provide greater noise interference resiliency than traditional FDM links
		d. All of the above statements are correct

QUESTION: Select the correct statement(s) regarding orthogonal frequency division multiplexing (OFDM).

		a. OFDM is a multicarrier modulation concept where user data is transmitted over several subcarriers in parallel
		b. OFDM subcarriers are not separated by guard channels (i.e., subcarriers overlap one another in the frequency domain)
		c. while OFDM signals spread user signals across a wider frequency spectrum, it is not considered a spread spectrum technique
		d. all of the statements are correct