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  • Moncure-NXDN-20091117A.ppt

    1. 1. The Rebirth of LMR A Presentation for the Radio Club of America 100 th Anniversary Symposium, November 21, 2009 Presented by Peter Moncure, VP RadioSoft 8900 Dick’s Hill Parkway Toccoa, GA 30577 [email_address]
    2. 2. In this presentation, I will: <ul><li>Describe NXDN </li></ul><ul><li>Discuss its latest advancements </li></ul><ul><li>Explore the possibilities for local radio shops of true IP-based LMR </li></ul><ul><li>Suggest strategies </li></ul>
    3. 3. What is NXDN? From Wikipedia: “ NXDN is a Common Air Interface (CAI) technical protocol for mobile communications. It was developed jointly by Icom and Kenwood. A NXDN Forum was formed in order to promote the NXDN protocol in North and South America.” There are currently eleven members, among which are Daniels, Icom, Kenwood, Ritron, Trident and a software provider, Etherstack. NXDN is implemented by Icom in their IDAS system and by Kenwood as NEXEDGE.
    4. 4. What is NXDN? <ul><li>Developed from Amateur Radio’s D-Star </li></ul><ul><li>Bitrate (DV mode) improved from 2.4 kbps to 4.8 kbps </li></ul><ul><li>Underlying IP connection protocol </li></ul><ul><li>Allows simultaneous digitized voice and data (950 bps) </li></ul>Image courtesy Icom
    5. 5. What is NXDN? <ul><li>The digital NXDN can be either 12.5 kHz or 6.25 kHz wide. </li></ul><ul><li>Two NXDN 6.25 kHz systems can fit within one 12.5 kHz channel. </li></ul>Note: in this example, the frequency centers are 3.125 kHz offset from FCC designated channel center frequency Image courtesy Icom
    6. 6. What is NXDN? <ul><li>Channels can be allocated as voice/voice, voice/data, or data/data. </li></ul><ul><li>NXDN also supports mixed analog FM and digital NXDN equipment and direct radio-to-radio communications. </li></ul><ul><li>Systems may be gradually migrated to digital narrowband. </li></ul>Image courtesy Icom
    7. 7. What is NXDN? <ul><li>4-level frequency-shift keying (FSK) modulation. </li></ul><ul><li>Digital audio uses the AMBE+2 vocoder. </li></ul><ul><li>Better weak-signal voice than analog FM. </li></ul><ul><li>Has wider range and slightly better multipath than analog FM </li></ul><ul><li>Data transmission bit rate 4.8 kbps. </li></ul>Image courtesy Icom
    8. 8. What is NXDN? Technical Characteristics The following FCC emissions apply to NXDN transmissions: 8K30F1E 12.5 kHz single channel digital voice 8K30F1D 12.5 kHz single channel digital data 8K30F1W 12.5 kHz single channel digital voice and data 4K00F1E 6.25 kHz single channel digital voice 4K00F1D 6.25 kHz single channel digital data 4K00F1W 6.25 kHz single channel digital voice and data 4K00F2D 6.25 kHz single channel analog CW ID The author has personally observed greater than 75 dB isolation from two adjacent NDXN 6.25 kHz-spaced channels, which essentially makes them location-independent.
    9. 9. The Icom IDAS ™ system <ul><li>Icom’s implementation of NXDN CAI </li></ul><ul><li>Permits IP packet switching without going to baseband audio </li></ul><ul><li>Allows PC nodes </li></ul><ul><li>Any PC can serve system-IP trunking </li></ul><ul><li>Requires ~13 kbps per connection </li></ul>
    10. 10. Icom IDAS intra-building radio service Image courtesy Icom
    11. 11. Icom IDAS cross-band IP radio service Image courtesy Icom
    12. 12. Icom IDAS system enables voting via IP Image courtesy Icom
    13. 13. What’s so great about NXDN? <ul><li>IP access cost already paid by user </li></ul><ul><li>Pricing locally determined </li></ul><ul><li>Only local maintenance costs required </li></ul>Networked LMR over IP pricing
    14. 14. What’s so great about NXDN? Networked LMR over IP Territory <ul><li>Ubiquitous, can use dialup for IP and satellite for RF </li></ul><ul><li>Can network any radio channel </li></ul><ul><li>Matches local propagation characteristic to available spectrum </li></ul><ul><li>Instantly reconfigurable </li></ul>
    15. 15. What’s so great about NXDN? Networked LMR over IP Hardware <ul><li>Any smartphone with a push-to-talk application </li></ul><ul><li>Any radio with a connected base station </li></ul><ul><li>Any PC </li></ul><ul><li>Packets well understood </li></ul>
    16. 16. Who can I talk to? <ul><li>Any participating user </li></ul><ul><li>Any smartphone user with a push-to-talk application </li></ul><ul><li>Any location with any radio channel </li></ul><ul><li>Any PC </li></ul>The LMR over IP Advantage
    17. 17. Why do I want it? <ul><li>Immediate, no dialing, ringing etc. </li></ul><ul><li>Conference calling always included, with balanced audio levels, no setup required </li></ul><ul><li>Setup may be done by LMR dealer, user or any third party </li></ul><ul><li>Familiarity in LMR situations </li></ul>The Push-to-talk Advantage
    18. 18. Hardware Software <ul><li>“ Smart” repeaters can now interface with all other smart devices: </li></ul><ul><ul><li>Smartphones (iPhone, Android, Windows Mobile) </li></ul></ul><ul><ul><li>PC’s, netbooks </li></ul></ul><ul><li>Smart devices may now act as radio nodes providing IP access </li></ul><ul><ul><li>Bluetooth, WiFi, etc. </li></ul></ul>Conceptual Convergence
    19. 19. Hardware Software <ul><li>Radios and repeaters will be automatically upgraded via IP and/or radio: new standard at </li></ul><ul><li>Channelization and modulation controlled </li></ul><ul><ul><li>By input radio signal </li></ul></ul><ul><ul><li>By software updates </li></ul></ul><ul><ul><li>By talkgroup server </li></ul></ul>Conceptual Convergence
    20. 20. Other Benefits of LMR-IP <ul><li>Immediate, no dialing, ringing etc. </li></ul><ul><li>Conference calling always included, with balanced audio levels, no setup required </li></ul><ul><li>Talkgroups can be assigned by LMR dealer, user or any third party </li></ul><ul><li>Familiarity in LMR situations </li></ul>Convenient
    21. 21. How to Build LMR-IP <ul><li>Create umbrella organization </li></ul><ul><li>Develop “smart” cards for repeaters </li></ul><ul><li>Enlist spectrum stakeholders </li></ul><ul><li>Market, market, market </li></ul>Strategy
    22. 22. Thanks <ul><li>Thanks for taking a look at the possibilities and promise of NXDN LMR over IP; </li></ul><ul><li>Thanks for not falling asleep during the last eighteen minutes; and </li></ul><ul><li>Thanks to all the folks at the Radio Club of America, who did all the behind-the-scenes work to this presentation possible. </li></ul>Questions? Interested, or know someone who would be? Call 706.754.2725 or write [email_address] to discuss any time, or check out