Voip enabled femtocell with a usb transceiver station

Abstract

Telephone calls between a mobile station (MS) and the mobile network or PSTN are routed through the Internet via VoIP using a femtocell, as opposed to the traditional macrocellular network. The femtocell can comprise a USB Transceiver Station that is connected to a personal computer through a universal serial bus port, which provides both power and a multi-megabit per second connection between the personal computer and the USB transceiver station. The USB transceiver station can comprise a microcontroller to manage signaling between the RF front end/baseband processor and the personal computer, as well as a precise timing mechanism to assist the synchronization of femtocell timing with the surrounding macrocellular network, if it is present. The USB transceiver station can have a compact form factor that that facilitates a high degree of portability by the subscriber, such as being readily attachable to their keychain.

1 - 20 . (canceled) 
     
     
         21 . A system for coupling mobile phone radio frequency signals with voice over internet protocol messaging, the system comprising:
 a voice over internet protocol client for sending registration messages from a base station, for maintaining a network address translation port binding between the base station and a server, for receiving a media frame from a mobile phone, and for receiving a call request from the server via the network address translation port binding;   a software defined radio for communicating with the voice over internet protocol client module, for processing and generating digital radio baseband signals, and for transmitting the call request to a mobile phone;   a voice over internet protocol gateway for receiving the media frame from the voice over internet protocol client, wherein the gateway transcodes the media.   
     
     
         22 . The system of claim  1 , wherein the mobile phone transmits the media frame using an adaptive multi-rate codec and wherein the voice over internet protocol gateway receives the media frame formatted according to the adaptive multi-rate codec. 
     
     
         23 . The system of  claim 21 , wherein the voice over internet protocol client uses a protocol selected from one of the following: session initiation protocol (SIP), inter-asterisk exchange protocol (IAX), and extensible messaging and presence protocol (XMPP). 
     
     
         24 . The system of  claim 21 , wherein the voice over internet protocol client receives the call request and transmits the media frame via the network address translation port binding. 
     
     
         25 . The system of  claim 21 , further comprising a set of configuration parameters for the base station, wherein the set of configuration parameters includes at least three of the following: a password associated with the base station, an address of the server, a port number of the server, a transmit frequency value for the base station, a mobile network code transmitted by the base station, and a registration interval. 
     
     
         26 . The system of  claim 21 , wherein the software defined radio is coupled to a radio front-end via a universal serial bus (USB) connector. 
     
     
         27 . The system of  claim 21 , wherein the mobile phone radio frequency signals are transmitted through a licensed radio spectrum and wherein an absolute radio frequency channel number is associated with a plurality of base stations. 
     
     
         28 . A system for providing voice service to a mobile phone, the system comprising:
 a server for receiving a registration message and a call-control message from a base station, wherein the base station communicates with the server using internet protocol;   a call-control processing unit for receiving the call-control message from the mobile phone and for translating the call-control message into a voice over internet protocol message;   a media processing unit for receiving a media frame from a mobile phone and for transmitting the media frame according to a format selected from real-time protocol and inter-asterisk exchange protocol;   a set of configuration parameters for the base station, wherein the set of configuration parameters includes a password, an address for the server, and a mobile network code transmitted by the base station.   
     
     
         29 . The system of  claim 28 , further comprising a voice over internet protocol gateway for receiving the media frame and information associated with the call-control message. 
     
     
         30 . The system of  claim 28 , further comprising a software defined radio for receiving signals from the mobile phone. 
     
     
         31 . The system of  claim 28 , wherein the call-control processing unit and the media processing unit operate on a personal computer, and wherein a radio front end connects to the personal computer via a universal serial bus (USB), and wherein the radio front end communicates with the mobile phone via radio frequency signals. 
     
     
         32 . The system of  claim 28 , wherein the base station transmits the media frame using forward error correction, and wherein a level of forward error correction is selected by measuring packet loss. 
     
     
         33 . The system of  claim 28  wherein the voice over internet protocol message includes at least one codec, and wherein a codec is selected from the at least one codec. 
     
     
         34 . The system of  claim 28  wherein the base station transmits the registration message to the server, the server transmits a challenge to the base station, and the base station transmits a hash value of the challenge and the password. 
     
     
         35 . The system of  claim 28  wherein the call-control message and the media frame are transmitted from the base station to the server using the same source user datagram protocol (UDP) port number. 
     
     
         36 . A computer-implemented method for coupling mobile phone signals with voice over internet protocol messaging, the method comprising:
 recording a set of configuration parameters for a base station, wherein the configuration parameters include an internet address of a server, a password, and a transmit frequency value;   registering a base station with a server using the password, wherein the base station transmits a registration request, the server transmits a challenge, and the base station transmits a hash value of the challenge and the password;   opening a network address translation port binding between the base station and the server;   receiving at the base station a media frame from a mobile phone, wherein the media frame is formatted according to a mobile network protocol;   transmitting from the base station the media frame to the server, wherein the media frame is formatted according to user datagram protocol.   
     
     
         37 . The method of  claim 36 , further comprising transmitting the registration request formatted according to a protocol selected from one of the following: session initiation protocol (SIP), inter-asterisk exchange protocol (IAX), and extensible messaging and presence protocol (XMPP). 
     
     
         38 . The method of  claim 36 , wherein the media frame contains media formatted according to one of the following codecs: global system for mobile communications (GSM) full rate, GSM enhanced full rate, adaptive multi-rate (AMR), and G.729. 
     
     
         39 . The method of  claim 36 , further comprising transmitting the call-control message and the media frame from the base station to the server using the same source user datagram protocol (UDP) port number.