3.1.5.1 Microwave Channels

The national microwave network in Iran has been expanding tremendously along with other telecommunication network sectors. The number of microwave channels increased by 26,527 in 1994, by 60,320 in 1995 and by 32,000 in 1997. As of March 1999, there were about 305,550 microwave channels in Iran. Table 3.7 shows the number of microwave channels in Iran for different sample years.

 

Table 3.7: Number of microwave channels in Iran.

Year	Number of Microwave Channels
1978	12,213
1986	27,716
1995	204,417
1997	272,000
03/1999	305,550

 

Moreover, the aggregate length of the microwave transmission lines was about 60,700 km in 1991, which increased to 65,287 km by 1997 and is expected to reach 137,000 km by the year 2000.

According to TCI's annual report, in 1997, the microwave network in Iran consisted of about 4,400 microwave stations and provided about 97% of the national long-distance services, showing almost 10% growth as compared with 1996 figures. The overall capacity of this network, 70% of which was digital, was about 137.5 million ch$\times$km for main routes and about 45.5 million ch$\times$km for spur routes.

One problem with the current microwave network in Iran is that except the T6 center in Tehran, which is based on Siemens technology, the existing systems can not provide effective and reliable service on all channels.