Review on the Millimeter-Wave Generation Techniques Based on Photon Assisted for the RoF Network System

Table 2

Comparison of different mm-wave generation schemes [5].

Schemes		Advantages	Disadvantages
DML [18, 22]		(i) Simple structure; (ii) Low cost	(i) Low frequency; (ii) Frequency chirping
External modulation [23, 27, 30]	Single modulator	(i) Simple structure; (ii) Low cost; (iii) MMW good performance	(i) Frequency limitation; (ii) Insertion loss
	Multiple modulators	(i) High frequency; (ii) MMW good performance	(i) Complicated structure; (ii) High insertion loss
Optical heterodyne [31, 34]		(i) Simple configuration; (ii) Low cost; (iii) Frequency generation flexibility	(i) Complicated light source; (ii) Frequency instability; (iii) Phase noise