Abstract:
An airborne cell phone in-flight entertainment (IFE) system uses a cell phone for calls and IFE requests by dialing appropriate numbers. A pico cell receives the calls and the IFE requests. A soft switch switches the calls and IFE requests according to the telephone number. A transceiver receives the calls from the soft switch and sends them to a ground station that directs them to a telephone system. A media server receives IFE requests and provides IFE to the cell phone. A direct broadcast satellite (DBS) receiver on the aircraft receives DBS signals. A transcoder converts the received DBS signals from one compressed video format to another. A broad-to-connection protocol conversion process receives converted format DBS signals and converts them to video content blocks, stores the video content blocks to a continuously updated buffer and presents them to the media server and then to the cell phone.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   The present application is related to application Ser. No. 11/151,090 filed herewith entitled “Global Cell Phone System and Method for Aircraft” by James P. Mitchell. The present application is related to co-pending applications Ser. No. 11/019,770 entitled “Protocol Bridge for a Wireless Entertainment Network” by James P. Mitchell filed on Dec. 21, 2004. The co-filed and co-pending applications are incorporated by reference and are assigned to the assignee of the present invention. 
   BACKGROUND OF THE INVENTION 
   The present invention relates to an in-flight entertainment (IFE) system, cellular telephone communications systems and specifically to an airborne cellular telephone communications system that is also used for IFE purposes to deliver programming to passengers. 
   Use of cellular telephones and other wireless data devices on board aircraft has been banned by the Federal Communications Commission (FFC) and restricted by the Federal Aviation Administration (FAA). The FCC ban is in place to avoid interference with terrestrial cellular systems while an aircraft flies over a cellular network. The FAS regulations restrict the use of cell phones on an aircraft to ensure against interference to onboard communications and navigation equipment. The FCC recently has announced that it is going examine relaxing its ban on cell phone use in aircraft. A relaxation in the FCC rules will still be subject to the rules and policies of the FAA and aircraft operators. 
   The FCC is proposing to permit airborne use of cell phone and other wireless devices at the devices lowest power settings under control of a pico cell located on the aircraft and only if such operation does not interfere with terrestrial cellular systems. In small cell phone networks pico cells are the smallest of radio cells. Pico cells often extend to just a few hundred meters in diameter in ground applications. Pico cells are used to fill in poor coverage areas or to augment larger micro cells or macro cells. On board an aircraft a cell phone user makes a call that goes to the pico cell. The pico cell then communicates from the aircraft to a ground station or to a satellite and from the satellite to a ground station and to finally connect to a public switched telephone network (PSTN). 
   The current state of the industry includes several cabin system integrators in the process of building and demonstrating pico cells on board aircraft including Honeywell, ARINC, Lufthansa, Air Cell, On Air and others. 
   Another problem that needs to be addressed in implementing an airborne pico cell system is the wide variety of cell phone models for the many different cell phone standards in use world wide. A passenger must be able to board an aircraft with the pico cell system and use his or her cell phone regardless of the model or type. 
   In-flight entertainment systems have been installed on commercial airliners for a number of years. An in-flight entertainment system typically comprises the components necessary to present entertainment, voice, data content to airline passengers and crew while in flight. Current IFE systems are wired systems that deliver programming to passengers similar to a cable television system. The current systems comprise head end equipment where programming and control functions originate, a distribution subsystem and display systems located at each passenger or crew seat. The entertainment content is distributed from the head end equipment to passengers by means of the distribution system. The display system receives the content from the distribution system, processes the content and displays it to the airline passengers. 
   Current IFE systems are best installed as an aircraft is being built. Existing aircraft may have retrofit systems installed. However retrofitting an existing aircraft with new wiring and cables is difficult and expensive. In addition wired systems are heavy due to the amount of wiring required to connect all the seats in an aircraft, comprise a large number of line replaceable units (LRU) such as distribution box equipment and seat equipment, and consume large amounts of power due to the large number of LRUs. Having a large number of LRUs also reduces reliability and increases cost. 
   Wireless IFE distribution systems offer many advantages over wired systems in an aircraft cabin. Retrofit installations on existing aircraft are much easier to accomplish due to the elimination of wires and cables. Finding locations for the many LRUs such as seat equipment is not required in a wireless system. Weight and power reductions are easily achievable with a wireless distribution system. Fewer LRUs result in less maintenance, more flexibility in IFE system installations, increased reliability, and reduced costs. 
   An aircraft presents a unique problem to serving video to cell phones not found with current commercial approaches. There is an expectation that one can view video for indefinite periods. Today&#39;s cell phones are not capable of continuously streamed video using the cellular infrastructure. Also there are issues with maintaining high enough quality of service over wireless links to support streaming video. There is also an expectation that one should be able to use audio services without competing with cabin noise sources. 
   Verizon recently released its V-Cast cell phone video service that can deliver high-quality video, however the service requires buffering time for each video clip. No continuous video streaming option is available. 
   Japan and other countries are producing cell phones that receive digital video via a separate integrated receiver. However this design does not serve the US due to differences in broadcast modulation technology. 
   A system using the proposed aircraft cabin pico cells and passenger cell phones is needed to provide a low-cost IFE system in contrast to current wired network solutions. The system must be able to function with the many models and types of cell phones in use. What also is needed in the system is a buffer that takes a live video stream and formats it for delivery to a cell phone. 
   SUMMARY OF THE INVENTION 
   An airborne cell phone audio/video in-flight entertainment (IFE) system is disclosed. The system comprises a cell phone for making a telephone call or an IFE request by dialing appropriate telephone numbers. A plurality of cell phones may be used in the system. A pico cell receives the telephone call and the IFE request from the cell phone. A soft switch switches the telephone call and the IFE request according to the appropriate telephone number. A transceiver receives the telephone call from the soft switch and sends the telephone call. A ground station receives the telephone call from the transceiver and directs the telephone call it to a telephone system service provider to complete the telephone call. A media server receives the IFE request and provides IFE to the cell phone through the soft switch and the pico cell. A satellite may be used to receive the telephone call from the transceiver and send it to the ground station. 
   The system may also comprise a direct broadcast satellite (DBS) for transmitting DBS signals and a DBS receiver for receiving the DBS signals. A transcoder connected to the DBS receiver converts the received DBS signals from one compressed video format to another. A broadcast-to-connection protocol conversion buffer receives converted format DBS signals and converts converted format DBS signals to video content blocks, stores the video content blocks and provides the video content blocks to the media server for connection-based deliver to the cell phones. The media server provides the video content blocks to the cell phone. 
   The media server provides stored IFE programming selected from the entertainment menu by a passenger at a cell phone. The media server accepts a call from the cell phone through the soft switch and provides an entertainment menu and travel information that is driven and updated by an aircraft position location system. 
   The media server uses a setup process to provide decoding and encoding of media between various cell phone formats. With this setup process the cell phone dials into the media server and selects performance parameters on a media server&#39;s website. The media server queries the cell phone for technical information including display format, protocol, and bandwidth requirements. The media server may determine cell phone capability by manual key-in entry on a cell phone key pad through a menu. The media server may automatically determine cell phone capability either directly from a cell phone protocol, control word, or inferenced automatically from a numerical identification of the cell phone where the numerical identification such as an electronic serial number is cross referenced to a model or cell phone type. The media server transcodes a video format from available video options to match the cell phone with different screen aspect ratios, frame rates, protocols, video players and a required data rate. The request results in a unique individually buffered video stream for the cell phone delivered from the media server. 
   When the cell phone initiates a call the media server performs an algorithm to detect quality of service (QoS) needs and directs the call through an appropriate available air-to-ground or SATCOM system according to a best match to the QoS needs of the cell phone. 
   It is an object of the present invention to provide a low cost, cell phone pico cell-based, in-flight entertainment system. 
   It is an object of the present invention to provide high quality and best effort audio and video programming and cell phone connectivity in an aircraft to passengers using cell phones. 
   It is an advantage of the present invention to provide an in-flight entertainment system that uses passenger carry-on cell phones. 
   It is an advantage of the present invention to provide an IFE system that is easily installed in an existing aircraft. 
   It is a feature of the present invention to offer a strategic opportunity to uniquely bring together most cell phone technology, in-flight entertainment server systems, and global satellite choices. 
   It is a feature of the present invention to be compatible with current third generation and future cell phone data exchange standards. 
   It is a feature of the present invention to be compatible with future generation protocols and video delivery methods including best effort unicast and broadcast methods. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may be more fully understood by reading the following description of the preferred embodiments of the invention in conjunction with the appended drawings wherein: 
       FIG. 1  is a block diagram of an approach under consideration to implement an airborne cellular network using a cabin pico cell; 
       FIG. 2  is a block diagram of the airborne cellular network of  FIG. 1  modified into a cell phone audio/video in-flight entertainment (IFE) system of the present invention; 
       FIG. 3  shows a voice/data and live TV embodiment of the present invention; and 
       FIG. 4  is a flow chart depicting a quality of service process operation of the present invention. 
   

   DETAILED DESCRIPTION 
   The invention described herein is for an aircraft in-flight entertainment system using a cabin cell phone pico cell and passenger provided cell phones to access audio/video content on the aircraft as well as for air-to-ground telephone use. 
     FIG. 1  shows an approach under consideration for approval by the FCC and being planned by several suppliers to implement an airborne cellular network  10 . An aircraft cabin pico cell  12  is used in an aircraft to provide an interface for a passenger cell phone  16  over an air-to-ground link to a cellular ground operations center  20 . The system  10  support many cell phones  16 . The pico cell  12  provides the functionality of a terrestrial cell and may function with CDMA, GSM, UMTS or other cell phone protocols and may be used for voice or data communications. A passenger places a call on the cell phone  16  that is received by pico cell antenna  13 , processed by the pico cell  12  and sent to a transceiver  14  and then to an aircraft antenna  15  for transmission to the cellular ground operations center  20 . At the ground operations center  20 , the call is received by a ground antenna  21 , passed to a ground transceiver  22  and then connected to a public switched telephone network (PSTN)  24 . Calls originating on the ground from the PSTN  24  follow a reverse path. Using this approach the power controlled low-power cell phone  16  avoids interference with terrestrial cellular telephone networks. The air-to-ground radio link may also be a satellite link that operates a frequencies that do not interfere with terrestrial cellular networks. 
   The airborne cellular network  10  of  FIG. 1  is modified into a basic cell phone audio/video in-flight entertainment (IFE) system  30  of the present invention as shown in  FIG. 2 . The system  30  is used for airborne cellular phone calls for voice and data communications as described above and for delivering audio and video-on-demand IFE programming to passengers with cell phones  16 . The cell phones  16  may also include such other devices as lap top computers (not shown) with wireless cellular transceiver cards and still be within the scope of the present invention. 
   Each passenger may receive independent content on their cell phone  16 . On board the aircraft the aircraft cabin pico cell  12  and pico cell antenna  13  of  FIG. 1  are utilized. A unique soft switch  31  selects between the pico cell  12  between an on-aircraft network media server  33  and the transceiver  14 . The soft switch  31  directs calls to connect to either the off-aircraft RF link using transceiver  14  or to the media server  33  to directly accept and provide media selections and accept control without the need for an external IFE system. 
   The transceiver  14  may communicate through the antenna  15  to a ground operations center  20   a  directly as before or though a satellite  37  in a SATCOM system. The ground operations center  20   a  may include a content provider  25  for providing programming to the aircraft. The audio/video programming delivered to the passenger cell phone  16  may originate in the media server  33  or come through the satellite  37  from the content provider  25  such as XM or Sirius Radio or a direct broadcast system (DBS) TV. 
   In operation of the system  30  in  FIG. 2 , a passenger carries on a cell phone  16  that is used as a terminal for enabling wireless access to the cabin cell phone pico cell  12  and to access the media server  33  using phone number addresses. The passenger places a call or a connection request to the media server  33  and the media server  33  delivers an entertainment menu with audio titles and listening content. The passenger makes a selection from the menu and requests the IFE programming. A pair of headphones  34  may be provided to the passenger for use with cell phone  16  so as not to disturb other passengers. 
   The media server  33  accepts the call or connection request from the cell phone  16  directed by the soft switch  31  and establishes a session with the client cell phone  16 , providing the entertainment menu and such information as travel advice, weather, hotel selection options, etc. that may be driven and updated by an aircraft position location system such as GPS, without the need for the client cell phone  16  to contact a ground Internet service provider (ISP). 
   The cell phone  16  may also be used to access the pico cell  12  and in turn connect to the media server  33  for viewing video-on-demand using video and audio streaming capabilities of the cell phone  16 . The video programming may originate from the media server  33  to deliver low bit rate video-on-demand to the cell phone  16  from stored video sources within the media server  33 . 
   Technology trends are constantly showing improvements in video CODECS and cell phone bandwidth. Industry predictions show next generation cell phone technology as supporting good quality video. This will become an option for future video entertainment where there are few options today. The client cell phone  16  may be used as a RF cabin link to the pico cell  12 , the pico cell  12  in turn is networked to the common media server  33  for offering either TCP (transport control protocol) or streaming UDP (user datagram protocol) video content to the client cell phone  16 . 
     FIG. 3  shows a satellite voice/data and live TV system  40  embodiment of the present invention. A SATCOM satellite  37   a  is used for voice and data communication between the ground and the aircraft and a direct broadcast satellite (DBS) TV satellite  37   b  is used for delivering live TV in-flight entertainment to the aircraft. The satellite  37   b  may be a DBS satellite such as DirecTV or Dish Network with the ground operations  20   a  providing DBS programming from the content provider  25 . In the live TV system  40 , passengers are conveniently provided a telephone number with which they can optionally dial directly into the aircraft media server  33  to watch live TV and listen with the headset  34  or may optionally telephone a ground number. Server telephone numbers may be placed in in-flight magazines or on seat back card. A plurality of cell phones  16   a ,  16   b ,  16   c ,  16   d  and others not shown may be used for live TV, movies, audio, games, and other IFE as well as for telephone calls for voice and data communications with the ground. 
   Calls from the plurality of cell phones  16   a - d  are made to one or more cabin pico cells  12  that have antennas  13 . The pico cells  12  may be distributed throughout the aircraft cabin to provide coverage to all cell phones  16  in all passenger seats. Calls from the pico cells  12  are directed to a SATCOM transceiver  14   a , or the direct air-to ground transceiver of  FIG. 2  or to the onboard media server  33  by the soft switch  31  as determined by the passenger&#39;s choice of service and number called. The SATCOM transceiver  14   a  is used in place of the transceiver  14 . 
   The soft switch  31  is a unique system that can deliver packet or streaming data and establishes network connections according to off-board or on-board aircraft needs such as demand for an off-board telephony link or on-board media entertainment from the media server  33 . The soft switch  31  may be implemented as a standard computing platform running switching software or as hardware switch. It is noted, that while the term soft switch is commonly used in industry and in this description, the component can be incorporated into another system and labeled differently, e.g. such as a media server with a switch, or other system performing the functions specified. 
   The soft switch  31  has the ability to scan and filter certain transported data to and from the cell phones  16 . The soft switch  31  is also in a unique system position to directly monitor/inject data and data streams to and from cell phones  16  using enunciator  31   a . Injected audio or video messages may include advanced warning to the passengers or crew that the plane will be landing soon. These messages are stored within the soft switch  31  and injected directly as a priority into a passenger audio/video stream. The message may be triggered or enabled by a position location data signal. Soft switch priority messages may also include the enunciator  31   a  telling the passengers or crew the status of the satellite links. 
   The soft switch  31  may also regulate data flow rate between the media server  33  and cell phones  16  through interface  31   b  to avoid favoring one or more clients over others that are sharing the network  40 . Data throughout is therefore kept at a stable rate to all cell phones  16  thereby avoiding video or audio CODEC starvation at any cell phone  16 . 
   The soft switch  31  may also intercept and scan each packet from the cell phone packet transport to identify unique control words that may be used to directly control the media server  33  through interface  31   b . For example, the “up-arrow” control word on the cell phone&#39;s keyboard may be detected directly by a soft switch algorithm (while scanning for codes) during it&#39;s otherwise normal switch routine. These control codes may be interpreted by an algorithm embedded within the soft switch  31  and used to control the cell phone&#39;s media stream such as switching the source to a new satellite channel or selecting a new video from a list of recorded videos. Each aircraft passenger client with his/her cell phone  16  has the capability to independently request a unique video—e.g. video-on-demand (VoD). 
   Messages delivered or injected by the soft switch  31  have very low latency, therefore the passenger does not hear an undesirable echo when the flight attendant makes an announcement. Passengers hear low-latency messages with their headsets  34  and also through the headsets  34  they can hear a public address (PA) message over PA speaker  35  in phase with the audio from the headset as interrupted audio. 
   A noise cancellation process may be used with the soft switch  31  that includes continuous measurement of cabin noise by a noise sensor  32 . A noise cancellation algorithm  31   c  uses the noise sensor  32  output to reduce noise of the digital output from the soft switch  31  to the SATCOM transceiver  14   a  by using phase cancellation. Soft switch  31  and pico cell  12  inherently introduce latency in the audio, uniquely enabling the application of a noise cancellation process without adding additional latency. 
   A cell phone  16   d  becomes a terminal for passenger control without interfering with other passenger seats by using position location identification obtained from manual entry on the cell phone keypad, use of a passenger ticket number, or use of a short range RFID tag  38  (See  FIG. 3 ) embedded near or in the seat. The passenger seat area has miniature short range RF tags (e.g. 20 cm RF range) that may be actively or passively excited by the cell phones  16  placed within their proximity. The RF tag data may also be received by the cell phone  16   d  and supplied to the soft switch  31  and sent to the media server  33  for processing lighting and environment control commands with algorithm  33   b  from the cell phone  16   d  to a specific aircraft seat enabling control of a light  39 . 
   Calls from the SATCOM transceiver  14   a  and antenna  15   a  go through the SATCOM satellite  37   a  to the ground operations center  20   a  where the calls are received by the antenna  21  and ground transceiver  22  and sent to the PSTN  24  through a service provider  26 . The SATCOM transceiver  14   a  and SATCOM satellite may be part of a low earth orbit (LEO) satellite system such as Iridium or a geosynchronous earth orbit (GEO) satellite system such as Boeing&#39;s Connexion Ku and/or Ka band satellite. Two or more SATCOM transceiver systems may be provided for operation with two or more different SATCOM systems. 
   A position location data interface, such as ARINC  429  or GPS in  FIG. 3 , provides the soft switch  31  position data enabling the system  40  to monitor satellite availability and to initiate system receiver and antenna handoff control. 
   Calls that request in-flight entertainment from the passenger go to the media server  33  from which stored or live entertainment is provided. The entertainment may be stored on RAID (redundant array of independent discs) discs and may be audio, games, or video stored thereon. Live audio may come from an XM or Sirius satellite receiver (not shown). 
   Live TV may come from DirecTV, Dish Network, SES Astra, hybrid Ka/Ku systems, or others from the content provider  25  in the ground operations center  20   a  over the DBS satellite  37   b  to a DBS antenna  15   b  and DBS TV receiver  14   b  onboard the aircraft. The output of the DBS satellite receiver  14   b  may be MPEG-2 compressed video that is converted to MPEG-4 compressed video in MPEG transcoder  36  to obtain a lower bit rate video signal. MPEG transcoders  36  are known in the art and are commercially available. The MPEG-4 video is sent to broadcast-to-connection protocol conversion buffers  35  here the video is converted from streaming video to video blocks that are temporarily stored before being supplied when needed to the media server  33  and finally to the cell phones  16   a - d.    
   U.S. Patent Application for “Protocol Bridge for a Wireless Entertainment Network” by James P. Mitchell Attorney Docket No. 04CR104/KE Ser. No. 11/019,770 filed on Dec. 21, 2004 and assigned to the assignee of the present invention and incorporated by reference is for a broadcast-to-connection protocol conversion buffer  35 . The video content processing buffer disclosed in the co-pending application provides streaming video content to the cell phones  16  and includes a video content buffer system configured to receive streaming video and store the receive streaming video as video content blocks. A video content processing engine provides video content blocks to the cell phones  16 . 
   The system  40  of the present invention has an important feature for solving video format compatibility issues as well as solving performance issues relating to the use of different cell phone technologies in one system. This will become a greater issue with time as cell phone manufacturers and network service providers expand into their own directions to differentiate and remain competitive. 
   A unique function associated with the media server  33  is that it provides all necessary decoding and encoding of media between various cell phone formats. This function is a generic system level operative and includes current, planned and future, standards and interfaces for audio and video including but not limited to analog, PCM, MPEG-X, H.324, H.263, G.723, V.80, H.3xx video teleconferencing, and others including standards formulated by the WAEA (World Airline Entertainment Association) content group. 
   Before launching a video stream, a setup process is automatically provided or initiated where a client cell phone  16  dials into the media server  33  and selects performance parameters on a media server&#39;s website. The setup process with the media server  33 , results in a technical information query of the cell phone  16 . Information including display format, protocol, and bandwidth requirements may be exchanged for the purpose of providing an optimal video experience. This setup process to determine a passenger&#39;s cell phone capability may be done by manual key-in entry through a menu from the cell phone key pad and decoded at the media server  33 . The setup process may also be automatic if allowed by the cell phone  16  either directly from the cell phone protocol, control word, or inferenced automatically from an electronic serial number (ESN) or mobile serial number (MSN) identification of the phone where the number is cross referenced to a model or phone type. The media server  33  then generates an acceptable video format to correctly match various phones with different screen aspect ratios (16×9, 5×4, etc), frame creates, video players and required data rate. 
   A request for video then results in unique individually buffered video streams for each client cell phone  16   a - d  and is delivered through the soft switch  31  located between the video media server  33  and the pico cell  12 . The system  40  accepts MPEG satellite video from the external Ku-band antenna  15   b  and produces the required number of individual buffers uniquely prepared for each client&#39;s unique cell phone  16   a - d  and application needs ad determined in the setup process. From start to finish the video content has been transformed from a broadcast or UDP format, to a TCP format for each cell phone  16   a - d  attached to the wireless pico cell system  12 . 
   Cell phones  16  today are just beginning to enable high-speed data usage. The future will have even faster data needs with 2.5 and 3G phone data needs already requiring 80 kbps to greater than 1 Mbps. This far surpasses current aircraft voice and data telephony capability. Existing SATCOM telephony systems (Iridium, Inmarsat, Globalstar, NATS-2 etc.) are not yet capable of meeting high performance needs for carrying data from the 3 G data enabled cell phones. This issue is compounded when multiplied by airplanes of users in a region of having multiple airplanes. Furthermore current services simply are not economical to the average consumer. 
   With the system  40  of the present invention, when a cell phone  16  or other wireless device on board the aircraft initiates a call, an algorithm  33   a  that can be performed by media server  33 , detects phone quality of service (QoS) needs and directs the call through an appropriate available air-to-ground or SATCOM system according to a best match to the QoS needs of that user and aircraft position location from the position location input shown in  FIG. 3 . 
   A flow chart depicting QoS process operation is shown in  FIG. 4 . The cell phone  16  is turned on and a call is made at step  41  and QoS process is started. At step  42  the ESN or MSN are delivered over a cellular system control channel. At step  43  the pico cell determines quality of service (QoS) needs from a QoS indicator from the cell phone  16 . If a voice call is needed at step  44 , the QoS indicator goes into an algorithm that directs the call to a low earth orbit (LEO) system such as Iridium as indicated by step  45 . Since voice is the only need, 2.4 kbps is sufficient as provided by the Iridium system. Alternatively at step  44  if the user has a 3G data phone and wishes to send a graphics attachment that requires high speed data, the QoS algorithms detects the type of service needed and directs the call through a geosynchronous earth orbit (GEO) satellite such as a two-way Ka or Ku band satellite (step  46 ). If the user requests a movie from the media server  33  at step  44 , the user request is routed to the media server  33  for stored movies, Internet, or satellite video at step  47 . At step  48  authorization is waited for. Step  49  enables the selected service from step  45 ,  46 , or  46  when authorization is received. At step  50  data communications begis until completion at step  51 , end of session. 
   It is believed that the cell phone audio/video in-flight entertainment system of the present invention and may of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages, the form herein before described being merely an explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.