Technology 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.