First standard for digital TV distribution over the coaxial cable (DVB-C) was published in 1994 and slowly started to replace analog cable TV worldwide [1], [2]. It has found application in various networks such as larger community antenna/access TV networks (CATV), smaller satellite master antenna TV systems (SMATV, Fig. 7) as well as hybrid fiber coax networks (HFC). This standard utilizes Reed Solomon codes to encode a transport stream which carries MPEG-2 or MPEG-4 coded video among others and which afterwards is modulated by quadrature amplitude modulation (QAM).
In order for cable operators to stay competitive with other satellite and terrestrial TV operators, to use available bandwidth more efficiently and to provide more TV channels and new services to users DVB-C2 standard [9] was defined (2008).
Besides SD and HD TV broadcasting this standard can also provide users with innovative interactive (IP) services (e.g. video on demand). As with DVB-T2, DVB-C2 also implements LDPC + BCH for FEC functions as well as the OFDM modulation with modulation schemes 16- to 4096-QAM to achieve 30% increase in transmission (spectrum) efficiency.
For example, when 4096-QAM modulation is used on 8 MHz bandwidth bitrates up to 83.1 Mbit/s can be achieved.
DVB-C2 signal can be adapted (optimized) for various network conditions and requirements because it supports a lot of modes and options. It is expected that both standards (DVB-C and DVB-C2) will coexist for many years.