NXDN CAI, Now accepted worldwide.

JVCKENWOOD Corporation (http://www.jvckenwood.co.jp/en/) announces that the NXDN Common Air Interface (CAI) was accepted at the Study Group 5 (SG5) meeting of the International Telecommunications Union Radiocommunications Sector (ITU-R) held in November 2016 and in Report M.2014-3, published in February 2017. This inclusion is highly significant since it represents official recognition – by the organization in charge of international standards – of NXDN as an international digital land mobile system, paving the way for its even wider adoption on a global  scale.

NXDN is an open standard narrowband digital protocol employing 6.25 kHz and 12.5 kHz FDMA technology to comply with frequency coordination requirements in many countries; it supports a comprehensive radio system including trunked, non-trunked and direct mobile-to-mobile communication. NXDN was developed by JVCKENWOOD in cooperation with Icom Incorporated to offer an alternative for the Land Mobile Radio (LMR) industry that would facilitate development of more affordable digital radio products that would satisfy the FCC narrowbanding mandate. It is also intended to help countries that lack sufficient frequency resources for their public safety agencies and business operators.

This future-proof protocol offers numerous advantages. For example, 6.25 kHz dual-channel systems can  be configured to fit within a 12.5 kHz channel, effectively doubling spectrum efficiency compared to an analog FM system occupying the same channel. Two NXDN channels can be allocated as voice/voice, voice/data, or data/data. Compared to analog FM, it provides wider coverage and superior multipath characteristics, but at the same time NXDN systems support mixed digital/analog operation, thus facilitating smooth migration to a narrowband digital system. With these and other advantages such as clear voice quality and strong security, it has proved highly successful and the number of NXDN radio terminals supplied into mission-critical non-mission critical applications has grown rapidly. NXDN has truly become a leading digital protocol for mobile communications.

NXDN is implemented in the KENWOOD-brand NEXEDGE product range, which since 2008 has offered digital conventional and trunked radio solutions to meet the diverse requirements of a wide range of government and industry users. And 2015 saw the debut of Gen2, the second generation of NEXEDGE products, with enhanced features, flexibility and performance – including the capability of linking up to 1,000 sites or 24 networks. NEXEDGE solutions are leveraging the full potential of the NXDN protocol, now officially recognized by the ITU.

About JVCKENWOOD

JVCKENWOOD Corporation is a global manufacturer specializing in Automotive and Professional System Solutions. It was reborn as one company in October 2011 through the merger of Victor Company of Japan, Limited (JVC) and Kenwood Corporation (Kenwood) three years after management  integration.

JVCKENWOOD operates four business segments, Car Electronics, Professional Systems, Optical & Audio, and Entertainment Software with image, sound, and radio technologies, as well as infotainment and visual software. JVCKENWOOD creates excitement and peace of mind, while aiming to achieve profitable growth and become a business group that is widely trusted by  society.

Note from the mentors

Good Day to all,
I want to make something clear that has come to my attention. When there are new users coming on board and the UID Or Talk Proceed Tone, or wrong group SELCALL PTT is used, please, don’t condemn these folks.
They are new members just like we all were at one time or another to NXDN. Promote this network like it is the best thing you have going. You use it, locally or on 65000, promote this network for more users and owners. 52 sites listed and only 39 on the network,
this is not a COUNTRY CLUB exclusive network folks. We promote the use and experiments of NXDN because it’s becoming the normal mode easily to acquire for some people. Just like DMR, but we hold ourselves a little higher than that side of
Digital. Digital is here and will be here for the long haul. Let’s not get in a twit over a Talk Proceed Tone, or dupe ID’s or wrong talk group setting in the PTT SELCALL. Help them out professionally. Because that is what we do.

I am super busy with commercial work I am about ready to explode. Your help to this makes things go better, and get stronger. I am still working with an independent group to create a software bridge between the Icoms and Kenwoods so we can patch 65000 back together. Right now asking for free help is very light, and this group I have approached is tied up with high level Stuff that makes their paychecks. Hang in there, it is in the works.

Let’s keep this rolling strong, 2 new repeater owners have joined the network, Ohio and another Canada station returned.

Thanks all. Seriously.

PS, look for the network to get a boost from hamradio2.0 as the editor has purchased a radio and will be doing some highlights on NXDN and Ham Radio. So yes, other people may not be talking, but they ARE LISTENING!

Evans Mitchell KD4EFM

 

Hello from KD4EFM, Evans; 2017 Jan 22

Greetings one and all Hams!

Orlando Hamfest coming up in February, I will be there! Hopefully I can show off the NX-5000 series radios while there as well.
News:
Well, work has had me rather busy over the last 3 months, so I can’t really give a good update on what has been going on, but will pass this along.
NXREF and NXCORE will be getting a minor over-haul and some updates to them. For the NX-REF, I am working on re-tooling it to become a soft-bridge between the Icom and Kenwood IP infrastructure. Thus making it a bridge between the two platforms.
NX-Core is being looked over to improve a few functions and make it a little more versatile for the NXDN side of Digital Ham Radio.

At this time, there is no lead-in as to designing NX-Ref to interface into the DMR Network Breinmaster. YES, there will be experiments leading up to an interface, but will not be part of the CORE NXDN world wide network.

DV-MINI’s; My understanding is there are a few who are playing with the mini and have been able to link into the NX-Core with the home-brew NXDN hotspots in non-nxdn repeater areas. Looking to incorporate that into the next level release forthcoming.

Anyone who has articles or other items to add, please send them to me or to Cliff (K1IFF)
and we will get them posted here for others to read up on.

New Repeaters?
I am getting word here in Florida, two repeaters have been put up over in Brevard County
on VHF.  I will work on getting that information updated in the repeater list linked over on the right side menu.

73’s and Happy Digital Ham’ing

Evans Mitchell
KD4EFM

Hello from Evans; KD4EFM

Greetings and welcome to the NXDN Ham Radio Blog. Wanted to update a few thing and share a link.

We are working on designing a software “bridge” between the Kenwood’s and Icom’s. We now have several “core servers” around the U.S. with 2 of them here in Florida. If you’re interested in joining the NXDN network, please let me know and I will get you the information you need. We welcome any BRAND of NXDN manufacturers and encourage you to join the network, EVEN YOU WEST COAST PEOPLE OVER YAWNDER and ya’ll friends to the north of the border.

NXDN repeater search engine, well, thanks to repeater book, they now have a good listing of these around now. Here is the link to hit it up. (82 KNOWN NXDN systems out there)

I have been rather busy on the commercial side of Kenwood Type C trunking, putting up a few sites here and there, and working on getting our 36th site prep’ed and ready to go.
Hope you all have had a safe and great summer, fall is round’ the bend now. Know of any other NXDN’ers out there, spread the word. There is NO conFUSION that we run a great network here, and we keep things simple. We just let the one’s and zero’s flow!

73

Evans Mitchell
KD4EFM

Problem reporting / bug tracking

A new bug tracking database is now online at:

http://rtcubed.com/nxcm/my_view_page.php

This database will be used for NXCore Manager feature requests, as well as problem reporting.  The goal is to be able to track problems and requests to closure with an industry standard system.

The database is viewable and reports can be made without a login.  You can also request a specific login and password if you wish, but it is not required.  We wish for the database to be as transparent as possible, so everyone can see our progress and that this is a tool that is actively developed.

New NXCM Releases

The following code is now in the Github repository:

Kenwood NXCM:  Version 1.3.4
Icom NXCM:  Version 1.3.1

The updates should allow for better stability and reliability.  It is recommended to update to these new versions if you haven’t done so already.

 

Looking to the future

This has been an exciting week of additions to the network. Several more users, plus two new repeaters.  I believe we are gaining momentum, and with the addition of the database and updated logger, we are moving along quite nicely.  I have been part of or heard conversations on the air that went very well, with few glitches.  That isn’t to say we are 100%, but the reliability to me seems much better.

However, I believe it is prudent for me at this time to step back and work on some things that I think will help reliability at this point.  For instance, I need to figure out the rest of where OTAA is being sent in a transmission, and also how to decode information mid-stream.  As an example, right now NXDN Core Manager looks for a “preamble” that both Kenwood and Icom repeaters send out before the datastream from the radio that has information such as UID, GID, and RAN.  I have all the NXDN documents from the nxdn-forum website.  I just need to study the CAI (Common Air Interface) more.

So I’m hoping in the next major release to be able to extract more information from the datastream.  I think this will help the dropout problems that occur by being able to start up again if the preamble gets lost.  Also, I do want the tx_otaa switch to work properly, so that TG 65000 is kept clean.

This kind of hacking will take some time.  Also, understanding the CAI will help in getting a software solution working for translating between Kenwood and Icom datastreams.  If this translation can be achieved, our network can be fully hardware agnostic with repeaters.  We will no longer in CT need to recommend someone get a Kenwood repeater to stay compatible, for example.  Those who want to put a repeater on the network can just buy what is cheaper or easier to obtain.  I can’t guarantee I will figure out how to do this in software, but I’m going to try.  The idea here would be a software program that will talk between the Kenwood and Icom NXCM, and translate a talkgroup.  So this way a regional or statewide talkgroup is available to both hardware platforms.

My philosophy going forward is this:  I look at Amateur Radio as a “public commons”, a space given to us by the government for public use and benefit, not controlled by business interests.  In the same way, I look at the software and tools that I write as public as well.  I think we can have a network which puts quality above quantity of users, and is based on mutual cooperation.  I don’t see NXDN as competing with other modes, but I do believe we can lead by example in how we think about issues of spectral efficiency, intelligent routing, and network management.

I am thankful for what Evans, Cliff, Alan, and others got started, and I would like to keep the momentum going.  If you have ideas for the future, please share them.  If you have bug reports, let me know.  This isn’t my network, and I don’t want the impression that CT’s NXCM is THE only NXCM.  It is just one of several used to manage a statewide / regional group of repeaters, that we mutually tie together as appropriate.  Please keep in mind though that features that are “nice to have” are going to be lower priority at this point than things that I think affect stability.

So if you don’t see any updates for a few weeks, it is because I’m going to be taking a step back and looking carefully at the CAI and how I can do better in routing / decoding it.  As I figure things out and make improvements to the software, I will check things into the repository and report out to the mailing list.