April 2004 Packet Voice - ACP wgc7_wp9 1 Packet Voice Radio Alvin H. Burgemeister B-twelve Associates, Inc. Connexion by Boeing

April 2004Packet Voice - ACP wgc7_wp92 Push-to-Talk Voice Radio Packet Service – Each radio transmission may be defined as a separate packet of information Packet Service – Each radio transmission may be defined as a separate packet of information CSMA Protocol – Sender listens for a break in radio traffic, then presses the talk button CSMA Protocol – Sender listens for a break in radio traffic, then presses the talk button Half-duplex – Only one sender at a time on the channel Half-duplex – Only one sender at a time on the channel

April 2004Packet Voice - ACP wgc7_wp93 Aeronautical Voice Radio Radio channel per control sector – Aircraft must change channel at every crossing Radio channel per control sector – Aircraft must change channel at every crossing Party line – All stations on channel hear all transmissions (within range) Party line – All stations on channel hear all transmissions (within range) SELCAL – Used for HF and for AOC to reduce cockpit workload SELCAL – Used for HF and for AOC to reduce cockpit workload

April 2004Packet Voice - ACP wgc7_wp94 Packet Digital Voice New operational concept enabled by new technology New operational concept enabled by new technology –Digital voice encoding and compression –High speed data links air ground –Digital recording and playback of voice transmission –Automated queuing and retransmission of message

April 2004Packet Voice - ACP wgc7_wp95 Digitize and Packetize

April 2004Packet Voice - ACP wgc7_wp96 Route and Transmit

April 2004Packet Voice - ACP wgc7_wp97 Receive and Store

April 2004Packet Voice - ACP wgc7_wp98 Decode and Listen

April 2004Packet Voice - ACP wgc7_wp99 Advantages Pilot/Controller not CSMA protocol engine Pilot/Controller not CSMA protocol engine –Workload –Spectrum efficiency –Message integrity and delivery Repeat of misunderstood message Repeat of misunderstood message Optimum use of channels Optimum use of channels Optimum choice of radio link Optimum choice of radio link No party line No party line

April 2004Packet Voice - ACP wgc7_wp910 Challenges New concept of communications New concept of communications New human interface to use new capabilities New human interface to use new capabilities –Discrete address for each station –Controller visual correlation with audio No party line No party line

April 2004Packet Voice - ACP wgc7_wp911 Potential New Uses Security Security –Authentication –Encryption Voice over HFDL Voice over HFDL Simplified AOC Voice Simplified AOC Voice –No SELCAL or dedicated radio –Cockpit to Dispatch or Maintenance –Cabin

April 2004Packet Voice - ACP wgc7_wp912 Conclusions Packetized Voice has significant potential Packetized Voice has significant potential –Optimize radio spectrum –Reduce pilot and controller workload –Provide new capabilities New concept of communications New concept of communications –Research needed to integrate into environment –Need to overcome resistance to change