Method for controlling transmission mode of access node in ultra-dense radio network, and apparatus therefor

A centralized processor (CP) for controlling activation/deactivation of a plurality of access nodes (ANs), in a distributed massive MIMO system including the plurality of ANs and a plurality of terminals, the CP comprising:

• a processor;
• and
• a memory storing at least one instruction executed by the processor,
• wherein when executed by the processor, the at least one instruction causes the processor to:
• collect, from the plurality of terminals or the plurality of ANs, first information on which of the plurality of terminals is connectable, and determine a set of active AN(s) based on the first information;
• adjust connections between the active AN(s) and the plurality of terminals based on cooperative transmission constraints;
• calculate a first energy efficiency according to the active AN(s), and calculate a second energy efficiency in a state in which at least one AN of the active AN(s) is deactivated or activated;
• and
• in response to determining that the second energy efficiency is not improved over the first energy efficiency, maintain the set of active AN(s), and in response to determining that the second energy efficiency is improved over the first energy efficiency, update the set of active AN(s) by excluding or further including the at least one AN, and perform iteratively from the calculating the first energy efficiency and the second energy efficiency.

A distributed massive MIMO system, the distributed massive system comprising:

• a centralized processor (CP);
• a plurality of access nodes (ANs) connected to the CP;
• and
• a plurality of terminals being provided with services by the plurality of ANs,
• wherein the CP is configured to:
• collect, from the plurality of terminals or the plurality of ANs, first information on AN(s) to which each of the plurality of terminals is connectable, and determine a set of active AN(s) based on the first information;
• adjust connections between the active AN(s) and the plurality of terminals based on cooperative transmission constraints;
• calculate a first energy efficiency according to the active AN(s), and calculate a second energy efficiency in a state in which at least one AN of the active AN(s) is deactivated or activated;
• and in response to determining that the second energy efficiency is not improved over the first energy efficiency, maintain the set of active AN(s), and in response to determining that the second energy efficiency is improved over the first energy efficiency, update the set of active AN(s) by excluding or further including the at least one AN, and perform iteratively from the calculating the first energy efficiency and the second energy efficiency, and
• wherein each of the plurality of ANs is configured to collect information on which of the plurality of terminals is connectable from the plurality of terminals;
• report the collected information to the CP;
• and transitioning to an active state or an inactive state according to control of the CP.