▁attempt ▁to ▁increase ▁range ▁and ▁accommod ate ▁low ▁power ▁devices ▁in ▁frequency ▁bands , ▁or ▁channels , ▁within ▁the ▁terrest rial ▁television ▁broadcast ▁band . ▁Ch annels ▁that ▁are ▁in ▁use ▁by ▁a ▁nearby ▁television ▁transmit ter ▁are ▁identified ▁and ▁left ▁una ffect ed ▁while ▁channels ▁not ▁being ▁used ▁for ▁broadcast ing ▁television ▁can ▁be ▁allocated ▁for ▁use ▁by ▁We ight less ▁devices . ▁ ▁A ▁network ▁of ▁base ▁stations ▁communicate ▁with ▁the ▁Internet , ▁or ▁a ▁private ▁network , ▁in ▁order ▁to ▁pass ▁information ▁from ▁devices ▁to ▁a ▁computer ▁system ; ▁and ▁to ▁pass ▁information ▁back ▁to ▁the ▁devices . ▁The ▁down link ▁to ▁devices ▁uses ▁time ▁sl ots ▁( TD MA ) ▁and ▁the ▁u pl ink ▁to ▁the ▁base ▁station ▁is ▁divided ▁into ▁sub - ch annels ▁so ▁that ▁several ▁devices ▁can ▁communicate ▁to ▁the ▁base ▁station . ▁ ▁Communic ation ▁and ▁connection ▁▁ ▁A ▁base ▁station ▁transm its ▁a ▁We ight less ▁frame ▁which ▁is ▁received ▁by ▁a ▁few ▁thousand ▁devices . ▁The ▁devices ▁are ▁allocated ▁a ▁specific ▁time ▁and ▁frequency ▁to ▁transmit ▁their ▁data ▁back ▁to ▁the ▁base ▁station . ▁The ▁base ▁station ▁is ▁connected ▁to ▁the ▁Internet ▁or ▁a ▁private ▁network . ▁The ▁base ▁station ▁access es ▁a ▁database ▁to ▁identify ▁the ▁frequencies , ▁or ▁channels , ▁that ▁it ▁can ▁use ▁without ▁inter fer ing ▁with ▁terrest rial ▁television ▁broadcast s ▁in ▁its ▁local ▁area . ▁ ▁Us es ▁ ▁We ight less ▁is ▁a ▁wireless ▁communic ations ▁protocol ▁designed ▁to ▁connect ▁Sm art ▁Mach ines ▁to