Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

VHF Marine Band radios, protocol, radio communication theory, practical advice; AIS; DSC; MMSI; EPIRB.
Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Sun Jan 14, 2018 9:41 am

Jim--I like the AIS and GPS feature for the VHF radio. If I get a chartplotter which displays AIS on the chart, is there a need and benefit for this feature on the VHF radio?

I am in the market for both the VHF and the chartplotter, so just wondering: [is there is a need for or is there is a benefit to have a chart display on the radio itself if the radio is connected to an external chart plotter?]

Thanks,
Don
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS in VHF Marine Band Radios

Postby jimh » Sun Jan 14, 2018 10:45 am

Don--the chart plotter display on a radio is generally limited to a very small and somewhat crude representation of a plan position indicator (PPI) showing the rough range and bearing to targets. The existence of this feature does not mean you should forgo connection of the AIS data output from the radio to an electronic chart plotter.

Also, regarding the inclusion of a built in GNSS receiver, a VHF Marine Band DSC radio that has its own GNSS receiver built-in does not need to be interfaced to an external GNSS receiver to get automatic position updates; this simplifies the installation.

Based on reports from the USCG, an overwhelming majority of DSC distress alert calls originating from DSC radios lacked any position data, which is interpreted as a failure in the radio installation to provide a connection between the radio and an external GNSS receiver. By providing the radio with its own GNSS receiver, the radio should always have a current position available to use in any DSC transmissions.

By including the GNSS receiver with the radio, the radio becomes its own self-contained system. The radio will still be able to transmit a distress alert, even if other electronic gear on the boat fails. If the radio depended on an external GNSS receiver to provide position data, and that external device failed, then the radio would lose the ability to report its position.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in AIS Receivers in VHF Marine Band Radios

Postby jimh » Sun Jan 14, 2018 10:53 am

Regarding VHF Marine Band radios that have an internal Automatic Identification System (AIS) receiver built-in: the main advantage is the ability to share one antenna between the AIS receiver and the VHF Marine Band ship transceiver. Also, a radio with AIS receiver will usually provide a limited chartplotter function and a navigation computer function. Finally, the radio may provide for a simple method to place a DSC call to a vessel that is an AIS target on the radio.

If you are boating in an area with commercial ship traffic, having an AIS receiver will allow you to be aware of other vessels with an AIS transmitter that are within about ten miles of your boat. All larger ships are required to equip with AIS transmitters and continually broadcast their position. Because the built-in AIS receiver will be sharing your main radio antennas with the VHF Marine Band DSC radio, you can avoid the need for a second antenna to be installed; the main radio antenna will also give the AIS receiver good range of reception.

Typically VHF Marine Band radios that include an AIS receiver will also provide a mini-chartplotter that will show a polar plot of AIS targets relative to your boat. The radio will also typically provide a data output that can be connected to an external chart plotter. The external chartplotter can they display the AIS target vessels as an overlay on its electronic navigation chart.

It is also typical for VHF Marine Band radios with an AIS receiver to provide an navigation computer that will compute the closest point of approach (CPA) for any AIS target vessels based on their reported course and speed and your boat's present course and speed. This same function may also be provided in an external chart plotter.

A VHF Marine Band DSC radio with an internal AIS receiver may also provide a simple user interface for originating a DSC call to a vessel that is one of the AIS targets. This will eliminate the need to enter the vessel's maritime mobile service identity (MMSI) into the DSC radio by manual (and usually slow and awkward) methods.

Determination of the existence of a need to have an AIS receiver is only possible based on your location and the presence of commercial traffic. If you are in Idaho and boat on mountain lakes, there probably will be very few commercial vessels on the lake with an AIS transmitter to be received. If you boat near a busy ocean port, there will likely be dozens of vessels transmitting AIS data around you most of the time. The existence of a need for an AIS receiver has to be based on your own situation, and, of course, interest.

For a detailed look at a VHF Marine Band radio with internal AIS receiver, read my long, multi-part description of one at

Standard-Horizon GX2200
http://continuouswave.com/forum/viewtopic.php?f=13&t=3029

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Sun Jan 14, 2018 11:23 am

DON--if you want to make integration of a new VHF Marine Band DSC radio and a new chartplotter as simple as possible, consider getting a radio and a chartplotter that both have NMEA-2000 network support. This will make the electrical connection to exchange data between them much simpler for you. You will need to build a NMEA-2000 network to accomplish this, but it is not particularly difficult or expensive (about $100) to make a network.

If you do not interconnect the radio and chartplotter using NMEA-2000, you can use NMEA-0183, but be careful that the chartplotter supports NMEA-0183. Many lower-tier chartplotter products for recreational marine use are not supporting NMEA-0183; they often only have NMEA-2000. Conversely, most VHF Marine Band radios all support NMEA-0183, with only a few supporting NMEA-2000. Be sure to get a radio and a chartplotter that are compatible for interconnecting them.

Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Sun Jan 14, 2018 8:59 pm

Thanks Jim, very helpful. The Standard Horizon GX2200 was one I was looking at. I also like the Raymarine Chartplotters, the Axiom 7 or A78, I had a Raymarine on the 1991, so I'd like to get something I am used to already.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

porthole
Posts: 599
Joined: Tue Oct 27, 2015 9:57 pm
Location: Jersey Shore

Re: How AIS Targets Are Displayed On Radios and Chartplotters

Postby porthole » Mon Jan 15, 2018 8:48 am

The chart-plotters I have looked at do not have a AIS receiver built in, and I don't know of what benefit it would be anyway for the recreational boater.

I have the GX2200 interfaced with a Lowrance HDS Gen3 chart-plotter and multi-function display. Although the AIS targets are displayed on the GX2200, it is not really user friendly to use the data. In my installation the radios are all mounted overhead and are a pain to look at in detail since I need bifocals to read them, and it hurts my neck.

The AIS targets on my chart-plotter show up as small triangles, pointing in the direction of travel if moving. I can also display lines relative to the course the target is making. Tapping the target on the screen brings up a menu on the target displaying what ever data is entered into the targets AIS transceiver and the basic NAV info, course, speed, CPA etc. Some targets have only a MMSI number listed, and on the extreme, Ship's name, hailing port, where they are coming from and going to, type of vessel and cargo.

In my area, just south of the New York Bight, the entrance to New York channel markers are displayed as AIS virtual targets. I receive these AtoN's in my driveway, 22-miles away. It is my understanding that the AtoN's are not broadcasting the data, but rather land based radio stations are broadcasting the data, and instead of the the land based position info, the broadcast has the AtoN's exact geographic position, which obviously does not change.

And with a chart-plotter, it is simple enough to tap the screen and either navigate to, or away from the AIS target. Locally some of the head boats now have AIS transmissions. Now if you see them sitting on an area for a prolonged time you can get that fishing spot from five miles away instead of running up on them and grabbing the location.

Somewhere on the forum here I have the AIS use with the GX-2200 and the Lowrance MFD's
Last edited by porthole on Thu Jan 18, 2018 3:18 pm, edited 1 time in total.
Thanks,
Duane
1999 Outrage 21
1999 Yamaha SW Series II 200

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: How AIS Targets Are Displayed On Radios and Chartplotters

Postby jimh » Mon Jan 15, 2018 1:47 pm

ASIDE to PORTHOLE:

Chartplotters either properly AIS targets or or they don't, and it depends mostly on the chartplotter, but also on the data that has been received from the target. For example, if an AIS receiver has not received the name of the ship in the AIS broadcast, a chartplotter cannot display the ship by name. Similarly, if the AIS receiver has not received the ship dimensions, a chartplotter cannot draw the ship outline in detail. The amount of data being sent and how often it will be transmitted varies with the category of the ship, either Class A or Class B, and the speed it is moving.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Mon Jan 15, 2018 1:54 pm

Don--if I were starting from scratch and had no radio or no chartplotter, I am not sure what brands I would consider in regard to AIS reception.

I have been very satisfied with my Standard-Horizon radio, an older model without an AIS receiver built in. I would be tempted to get the GX2200 with AIS. It is an NMEA-0183 only device, but for me that is not any problem. I can interface NMEA-0183 with very little effort.

As for which chartplotter, SONAR, multi-function display to get--well the market is so full of great products, and new models are introduced all the time, that I really cannot say much about any of the latest models. My quite old, slow, and small HDS-8 first-generation device is still working. I paid $1,500 for it many years ago. I see that now you can get more in a multi-function display at that price point, but you can also spend $5,000 on one, too. I really don't know where to steer anyone. I'd say it is best to pick a price range, then compare what is offered at that price.

Don--if you like a particular Raymarine chartplotter and multi-function display, consider getting the radio from Raymarine, too. They will very likely be easier to integrate if you choose the same brand for both radio and chartplotter.

But--VERY IMPORTANT--if you choose the Raymarine Axion 7 be aware it does not have a NMEA-0183 port and cannot be easily interfaced with a radio that has only NMEA-0183 ports, like the GX2200. You will regret trying to pair up the Axion to the GX2200.

But if you stick with Raymarine line and get the Axion 7, to get a Raymarine radio with AIS I think you have to buy the very top-of-the-line RAY70 model, which would probably be expensive.

Just to be explicitly clear: I don't think buying a chartplotter that does not have NMEA-0183 is a good investment. I would prefer any chartplotter I own to have both NMEA-0183 and NMEA-2000 connections.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: How Chartplotters Show AIS Targets

Postby jimh » Mon Jan 15, 2018 1:56 pm

Don--if you want to see what AIS ship targets look like on an HDS-8 and other displays, then read my article about AIS:

AIS Ship Spotting
http://continuouswave.com/whaler/reference/AIS_ShipSpotter.html

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: How AIS Targets Are Displayed On Radios and Chartplotters

Postby jimh » Mon Jan 15, 2018 2:14 pm

ASIDE TO PORTHOLE:
porthole wrote:The chartplotters I have looked at do not have a AIS receiver built in...


I do not recall ever seeing a general-purpose chartplotter being set up with an integral AIS receiver. However it is quite common for there to be a chartplotter dedicated to showing AIS targets to have its own integral AIS receiver. Here are some examples:

VESPER Marine Watchmate 750 AIS receiver and display
https://www2.vespermarine.com/ais-watchmate-rx

COMAR Systems CSD300 AIS Colour Display Receiver
https://comarsystems.com/product/ais-colour-display/

It is also very common for an AIS transponder to have a dedicated chartplotter display. These are so numerous and common that to list them all would be a project.

But I rather doubt that DON is interested in anything like this. He is looking for a VHF Marine Band radio that has an AIS receiver and GNSS receiver built-in.

Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Mon Jan 15, 2018 9:06 pm

Thanks Jim, I can see your advice of not being able to connect the Standard Horizon to the Raymarine is good advice. I'll have to rethink my hardware.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Tue Jan 16, 2018 11:32 am

DON--I noted that in the specification for the AXIOM 7, Raymarine suggests that NMEA-0183 can be used if an NMEA-2000 adaptor is fitted; they say:
[NMEA-0183] [r]equires suitable adaptor to NMEA2000 network


The problem with that approach is as follows:

--the cost of a NMEA-018 to NMEA-2000 gateway is expensive; they are often $200 or more;

--the is no universal, complete translation of data; each gateway device can only translate a certain subset of all possible data between the two formats;

--in the case of a VHF Marine Band radio with NMEA-0183, the most important possible data to come from the radio will be data related to digital selective calling (DSC) Distress Alert calls, that is, the sentences DSC and DSE; although it is hard to believe, there is NO gateway product (that I can find) that handles that data. That means that the most important function in integrating the radio and chartplotter will be lost, even if you went to the trouble and expense of buying a gateway.

For all of the above reasons, I strongly discourage trying to integrate a VHF Marine Band DSC radio with a chartplotter by relying on use of a NMEA-2000-to-NMEA-0183 gateway device.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Tue Jan 16, 2018 4:05 pm

DON--I looked at the Raymarine line of AXIOM products. None of the models in the plain AXIOM line provide NMEA-0183.

From what I can tell from their website specifications, you would have to upgrade to the model AXIOM PRO 9 to have a NMEA-0183 port available from the chartplotter. The AXIOM PRO 9 models begin at an MSRP of US-$2,300.

ASIDE to DON: another important factor to consider when selecting a chartplotter is the electronic charts it can use. You should consider the type of charts available and their cost. Since you are in Atlantic Canada, the ability to use electronic charts from the Canadian Hydrographic Service (CHS) may be important to you. CHS publishes their electronic charts in both raster (BSB) and vector (S57) formats. From what I can tell, the Raymarine chart plotters cannot use those charts. However, they can use electronic charts of Canada published by Fugawi, called the "Fugawi Aboard Canada and bordering US States" chart bundle. It is a very comprehensive package of charts--over 7-GB of data--and only costs $99. That is a GREAT deal--the price of CHS official electronic charts with that same coverage would be thousands of dollars.

Another factor that is favorable for buying Raymarine: they maintain their own support website. You can post questions to the website about Raymarine products and get answers from Raymarine support technicians.

And, finally, you might consider that Boston Whaler has partnered with Raymarine as the electronics supplier for OEM installed electronics on Boston Whaler boats. That is another good endorsement.

Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Tue Jan 16, 2018 7:38 pm

Thanks Jim, we have a boat show coming up in Halifax, I'll be having a run around there to see what products are available. We also have a good marine shop that sell a lot on line, good prices, The Binnacle. I like the Raymarine, but not spending US$2300 on a chartplotter/MFD.

It seems to me the NMEA standard is evolving away from 0183 to 2000.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Tue Jan 16, 2018 8:52 pm

DON--NMEA-2000-only stuff seems to be oriented toward lowest-tier recreational grade electronics. The serious professional-grade stuff still provides NMEA-0183. I don't think it will be going away very soon.

porthole
Posts: 599
Joined: Tue Oct 27, 2015 9:57 pm
Location: Jersey Shore

Re: How AIS Targets Are Displayed On Radios and Chartplotters

Postby porthole » Thu Jan 18, 2018 3:34 pm

jimh wrote:ASIDE to PORTHOLE:

Chartplotters either properly AIS targets or or they don't, and it depends mostly on the chart plotter, but also on the data that has been received from the target. For example, if an AIS receiver has not received the name of the ship in the AIS broadcast, a chartplotter cannot display the ship by name. Similarly, if the AIS receiver has not received the ship dimensions, a chartplotter cannot draw the ship outline in detail. The amount of data being sent and how often it will be transmitted varies with the category of the ship, either Class A or Class B, and the speed it is moving.


I'm not sure what you are aiming at here, my first guess is that there are some words missing or misplaced (first sentence).

And I don't recall suggesting a chart plotter should display detailed info from an AIS receiver when an AIS ship board transmitter does not have their detailed data set into the AIS transmitter.
My example of one of the head boats using AIS in our area has only the MMSI number entered, one other head boat has the MMSI and the boat's name, but nothing more. As a result, all I see on the MFD display is the MMSI number (sometimes the name), coarse and speed.

I have also seen on some of the big boats that run off our coast a lot more data displayed, as mentioned previously, ship's name, hailing port, destination, dimensions and weight, sometimes cargo and of course the most useful data, coarse, speed CPA etc.

On my Lowrance MFD's the AIS displayed target does not change based on data received like you show on the Polar* software.
Thanks,
Duane
1999 Outrage 21
1999 Yamaha SW Series II 200

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Thu Jan 18, 2018 4:29 pm

porthole wrote:I'm not sure what you are aiming at here, my first guess is that there are some words missing or misplaced (first sentence).


DUANE--there are no missing words. Feel free to ignore my aside. It was in reply to your post mentioning how chartplotter display AIS targets. You brought up the topic when you said:

porthole wrote:The AIS targets on my chart-plotter show up as small triangles, pointing in the direction of travel if moving.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: How AIS Targets Are Displayed On Radios and Chartplotters

Postby jimh » Thu Jan 18, 2018 4:34 pm

ASIDE to DUANE:

porthole wrote:...I don't recall suggesting a chart plotter should display detailed info from an AIS receiver when an AIS ship board transmitter does not have their detailed data set into the AIS transmitter....


An AIS transponder can have all kinds of information programmed into it, but it does not always send all the data on every transmission. It only sends certain categories of information at certain intervals. If you want to start a thread on the details of AIS data transmission, we can certainly go into that topic in more depth. I don't find it really to be germane to this topic.

If your chartplotter never draws the entire ship outline (when available), it probably is not quite up to speed with proper AIS display.

porthole wrote:...On my Lowrance MFD's the AIS displayed target does not change based on data received like you show on the Polar[View] software.


My Lowrance HDS behaves like that, too. The AIS target is never drawn properly to its actual dimensions. That is a shortcoming of the Lowrance chartplotter. It might be interesting to survey other chartplotters to see how they draw AIS targets. I will start a new thread--see the new topic at

Display of AIS Targets: Vessels
viewtopic.php?f=13&t=3040

Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Tue Jan 23, 2018 5:46 am

Standard Horizon are bring out NMEA 2000 for a GX 6000 and GX 6500. I searched those numbers and found both on backorder for US$670 and US$1,070. Out of my price range for a VHF.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Thu Jan 25, 2018 12:10 pm

The future of the Standard-Horizon GX6n00 series seems to be a bit in doubt. It has been more than a year since they were announced, but still nothing on the market, nothing on the website, and nothing from the FCC about approval in the USA. I think that is why the Canadian website mentioned (above) says "backorder" status.

The fellow who was the most public face of Standard-Horizon, Jason Kennedy, has left the company. He was a very good point of contact for information. He also owned a Boston Whaler boat. Since Jason left, I have not heard any news about these radios.

jimh
Posts: 6895
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby jimh » Sun Feb 04, 2018 11:28 am

Don--re the Standard-Horizon GX6000 radio: it has just been approved by INDUSTRY CANADA, a government agency. See my remarks in the the other forum thread that is dedicated to the GX6000 radio.

GOOD NEWS FOR GX6000 RADIO
http://continuouswave.com/forum/viewtopic.php?f=13&t=1527#p17621

Don SSDD
Posts: 163
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: Advantages of Built-in GNSS and AIS Receivers in VHF Marine Band Radios

Postby Don SSDD » Mon Feb 05, 2018 6:51 pm

Thanks Jim.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia