Outline Personal Handy-phone System

phs japan 1997–2003 (willcom, ntt docomo, astel)

phs cordless telephone dect, capability handover 1 cell another. phs cells small, transmission power of base station maximum of 500 mw , range typically measures in tens or @ hundreds of metres (some can range 2 kilometres in line-of-sight), contrary multi-kilometre ranges of cdma , gsm. makes phs suitable dense urban areas, impractical rural areas, , small cell size makes difficult if not impossible make calls rapidly moving vehicles.

phs uses tdma/tdd radio channel access method, , 32 kbit/s adpcm voice codec. modern phs phone can support many value-added services such high speed wireless data/internet connection (64 kbit/s , higher), www access, e-mailing, , text messaging.

phs technology popular option providing wireless local loop, used bridging last mile gap between pots network , subscriber s home. developed under concept of providing wireless front-end of isdn network. base station of phs compatible isdn , connected directly isdn telephone exchange equipment e.g. digital switch.

in spite of low-cost base station, micro-cellular system , dynamic cell assignment system, phs offers higher number-of-digits frequency use efficiency lower cost (throughput per area basis), compared typical 3g cellular telephone systems. enables flat-rate wireless service air-edge throughout japan.

the speed of air-edge data connection accelerated combining lines, each of 32 kbit/s. air-edge 1× or first version introduced in 2001 provide 32 kbit/s service. in 2002, 128 kbit/s service (air-edge 4×) started. in 2005, 256 kbit/s (air-edge 8×) service started.

in 2006, speed of each line up-graded 1.6 times introduction of w-oam technology. speed of air-edge 8× 402 kbit/s latest w-oam capable instrument.

in april 2007, w-oam typeg introduced allowing data speeds of 512 kbit/s air-edge 8x users. furthermore, w-oam typeg air-edge 8× service planned upgraded maximum throughput of 800 kbit/s, when upgrading access points (mainly switching lines isdn fibre optic) in system completed. , may exceed speeds of popular w-cdma 3g service ntt docomo s foma in japan.

implementation

astel-brand phs base station in tokyo, japan

originally developed ntt laboratory in japan in 1989 , far simpler implement , deploy competing systems pdc or gsm, commercial services has been started 3 phs operators (ntt-personal, ddi-pocket, , astel) in japan in 1995 forming piaf (phs internet access forum). however, service has been pejoratively dubbed poor man s cellular , due limited range , roaming abilities. market share in japan has been declining , ntt docomo, has absorbed ntt personal, , astel terminated phs service in january 2008. other countries phs networks, have terminated offering phs services , migrated gsm.

wireless local loop (wll) systems based on phs technology in use in of above-mentioned countries. in recent years, willcom, formerly ddi-pocket, introducing flat-rate wireless network , flat-rate calling in japan, has reversed local fate of phs extent. in china, there seen explosive expansion of subscribers until around 2005, has been calming down in 2006. in chile, telefónica del sur launched phs-based telephony service in cities of southern part of country in march 2006. in brazil, suporte tecnologia has phs-based telephony service in betim, state of minas gerais, , transit telecom has announced rollout of phs network in 2007.

china telecom operated pas system in china, though technically not regarded allowed provide mobile services, because of particularities of chinese governance. china netcom, other fixed-line operator in china, provides xiaolingtong service. system runaway hit, on 90 million subscribers signed of 2007. largest vendors of system utstarcom , zte. however, low priced mobile phones rapidly replacing phs. ministry of industry , information technology of people s republic of china issued notices on 13 february 2009 both registration of new users , expansion of network discontinued service ended end of 2011.

a phs global roaming service available between japan (willcom), taiwan, , thailand.