What is a mid split system in cable tv?

Answer 1

CATV split systems allow two way communications over a single cable or path between devices transmitting downstream from a central location (headend) to the subscriber's cable box or modem. Those devices in turn transmit upstream to the headend to complete the two way link. The typical North American system is called a "sub split". The term sub means that the upstream path (5 to 42 MHz) is below 50 MHz which is also the lower end of the downstream path. A "mid split" pushes the upstream path out to 5 to 110 MHz on average for expanded upstream capacity. Mid splits are typically used for institutional or municipal networks that require equal bandwidth for both directions. The term "mid split" was designated at a time when CATV systems only ran out to 220 MHz, so it was an appropriate name for its time but it's stuck over the years as cable system bandwidth moved further out into the spectrum. The downstream on a "mid split" starts around 168 MHz. There's a third option called a "high split" which pushes the upstream path out to 5-174 MHz on average with downstream starting around 232 MHz.