Review and Progress towards the Capacity Boost of Overhead and Underground Medium-Voltage and Low-Voltage Broadband over Power Lines Networks: Cooperative Communications through Two- and Three-Hop Repeater Systems

Table 2

Five indicative underground distribution BPL topologies [3, 16, 20].

Denotation	Description	Number of branches; (N)	Lengths of distribution TLs [𝐿1⋯𝐿𝑁+1]	Lengths of branch TLs [𝐿𝑏1⋯𝐿𝑏𝑁]
Underground urban case A	A typical urban topology	3	[70 m 55 m 45 m 30 m]	[12 m 7 m 21 m]
Underground urban case B	An aggravated urban topology	5	[40 m 10 m 20 m 40 m 60 m 30 m]	[22 m 12 m 8 m 2 m 17 m]
Underground suburban case	A typical suburban topology	2	[50 m 100 m 50 m]	[60 m 30 m]
Underground rural case	A typical rural topology	1	[50 m 150 m]	[100 m]
Underground “LOS” case	“LOS” transmission	0	[200 m]	—