▁by ▁white ▁space ▁devices ▁( such ▁as ▁those ▁using ▁We ight less ). ▁A ▁range ▁of ▁mod ulation ▁and ▁encoding ▁techniques ▁are ▁used ▁to ▁permit ▁each ▁base ▁station ▁to ▁communicate ▁at ▁a ▁variety ▁of ▁spe eds ▁with ▁terminal s , ▁some ▁of ▁which ▁may ▁be ▁nearby ▁and ▁others ▁several ▁km ▁away . ▁Data ▁rates ▁may ▁vary ▁depending ▁on ▁the ▁distance ▁and ▁the ▁presence ▁of ▁radio ▁inter ference ▁– ▁the ▁typical ▁range ▁is ▁alleg ed ▁to ▁be ▁between ▁about ▁ 0 . 1 M bit / s ▁and ▁ 1 6 M bit / s . ▁The ▁design ▁of ▁the ▁air ▁interface ▁and ▁protocol ▁minim ises ▁the ▁costs ▁of ▁the ▁equipment ▁and ▁its ▁power ▁consumption . ▁A ▁broad band ▁down link ▁from ▁a ▁base ▁station ▁to ▁a ▁terminal ▁uses ▁single ▁car rier ▁in ▁an ▁un used ▁ 6   M Hz ▁( for ▁USA ) ▁or ▁ 8   M Hz ▁( for ▁UK ) ▁TV ▁channel . ▁ ▁Security ▁ ▁The ▁communic ations ▁link ▁between ▁the ▁base ▁station ▁and ▁the ▁devices ▁is ▁encrypted . ▁ ▁Dep loy ments ▁ ▁We ight less - N ▁networks ▁have ▁been ▁deployed ▁in ▁C open hagen , ▁Den mark ▁and ▁Es b jer g , ▁Den mark . ▁However , ▁there ▁seems ▁to ▁be ▁a ▁lack ▁of ▁client ▁hardware ▁for ▁We ight less ▁to ▁be ▁mass ively ▁used . ▁ ▁See ▁also ▁▁ ▁W im ax ▁Te lem etry ▁D ASH 7 ▁ ▁References ▁ ▁External ▁links ▁▁▁ ▁White ▁Space ▁Network s ▁and ▁Machine - to -