V-band backhaul operating at 60-80 GHz, the RF losses associated with radio and antenna connections are significantly reduced. Conventional point-to-point, LoS microwave systems operate in the licensed spectrum from C-band up to Ka-band. Common operating band frequencies are 6, 11, 18, 23, 26, and 38 GHz. These systems require unobstructed propagation. Fig. 1.42 illustrates a point-to-point micro- wave backhaul link connecting a macro-cell base station node to an aggregation node. For small-cell base station applications some microwave equipment vendors have demonstrated NLoS operation using conventional LoS microwave bands, leveraging high antenna gains with Table 1.3: Wireless backhaul options and associated parameters [79]. Single- Channel Channel Backhaul NLoS/ Frequency Licensed/ Bandwidth Range Latency Capacity Unlicensed (MHz) Modulation (Gbps) Application Notes Microwave C, Ku, Ka Licensed 3.5/7/14/ Macrocell High reliability and 28/56 small-cell high capacity links 10/20/30/ 16-2048QAM aggregation 40/50 mmWave Licensed 28/56/112 <0.05 0.3-10 Macrocell Narrow beams and 16-2048QAM small-cell oxygen absorption to Unlicensed > 250 aggregation improve frequency Lightly 250-5000 16QAM, 64QAM reuse in V band licensed C, Ku, Ka Licensed 26/33/50/ QPSK, 8PSK, Small cell Remote and rural 72/500 32ASK (medium areas with no earth infrastructure orbit) (GEO) NLoS/ Licensed/ 5/10/20/ 64QAM,256QAM Metro-cell, Fast deployment and 6 GHz unlicensed 40/80/160 (NLoS) picocell, unpredictable capacity femtocell (LoS) In-band LTE bands Licensed 5/10/15/ 64QAM > >10 Picocell, Occupies cellular relay 20/40 femtocell spectrum and adds latency 96 Chapter 1 Macro-cell site tail Macro-cell site aggregation node C, Ku, Ka band backhaul link fiber Macro-cell Microwave baseband baseband Core network Fiber backhaul Figure 1.42 A point-to-point LoS microwave link with a relay node and aggregation node [79]. operating guidelines for the electromagnetic wave propagation effects such as diffraction, reflection, and penetration to overcome t