PIANO: A power saving strategy for cellular/VoWLAN dual-mode mobiles

The integration of cellular and VoIP over WLAN (VoWLAN) systems recently has attracted considerable interest from both academia and industry. A cellular/VoWLAN dual-mode system enables users to access a low-cost VoIP service in a WLAN hotspot and switch to a wide-area cellular system without WLANs. Unfortunately, cellular/VoWLAN dual-mode mobiles suffer the power consumption problem that becomes one of the major concerns for commercial deployment of the dual-mode service. In this study, we present a novel power saving mechanism, called PIANO (paging via another radio), for the integration of heterogeneous wireless networks, and further apply the proposed methods to implement a cellular/VoWLAN dual-mode system. Based on the proposed mechanisms, a dual-mode mobile can completely switch off its WLAN interface, only leaving the cellular interface awake to listen to paging messages. When a mobile receives a paging message from its cellular interface, it wakes up the WLAN interface and responds to connection requests via WLAN networks. Therefore, a dual-mode mobile reduces the power consumption by turning off the WLAN interface during idle, and can also receive VoWLAN services. Measurement results based on the prototype system demonstrate that the proposed methods significantly extend the standby hours of a dual-mode mobile.

[1]  Paramvir Bahl,et al.  Wake on wireless: an event driven energy saving strategy for battery operated devices , 2002, MobiCom '02.

[2]  MishraArunesh,et al.  An empirical analysis of the IEEE 802.11 MAC layer handoff process , 2003 .

[3]  William A. Arbaugh,et al.  An empirical analysis of the IEEE 802.11 MAC layer handoff process , 2003, CCRV.

[4]  Jouni Mikkonen,et al.  Wireless LAN access network architecture for mobile operators , 2001 .

[5]  Giovanni Giambene,et al.  A performance evaluation approach for GSM-based information services , 2003, IEEE Trans. Veh. Technol..

[6]  Christian Bettstetter,et al.  Mobility modeling in wireless networks: categorization, smooth movement, and border effects , 2001, MOCO.

[7]  Mark Handley,et al.  SIP: Session Initiation Protocol , 1999, RFC.

[8]  Sajal K. Das,et al.  Mobility management for VoIP service: Mobile IP vs. SIP , 2002, IEEE Wirel. Commun..

[9]  Yi-Bing Lin,et al.  WGSN: WLAN-based GPRS Support Node with Push Mechanism , 2004, Comput. J..

[10]  Ramesh R. Rao,et al.  Combining paging with dynamic power management , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[11]  Suresh Singh,et al.  PAMAS—power aware multi-access protocol with signalling for ad hoc networks , 1998, CCRV.

[12]  BettstetterChristian.  Mobility modeling in wireless networks , 2001 .

[13]  Dominic Lenton.  Speaking of Wi-Fi , 2003 .

[14]  Randy H. Katz,et al.  Measuring and Reducing Energy Consumption of Network Interfaces in Hand-Held Devices (Special Issue on Mobile Computing) , 1997 .

[15]  B. Otis,et al.  PicoRadios for wireless sensor networks: the next challenge in ultra-low power design , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).