RTCM Paper 009-2010-SC101-245
Radio Technical Commission for Maritime Services
1800 N. Kent St., Suite 1060
Arlington, Virginia 22209-2109
www.rtcm.org
Telephone: +1-703-527-2000 Telefax: +1-703-351-9932
December 8, 2009
SUMMARY RECORD
Meeting of RTCM Special Committee 101
and Special Committee 110
GPS-equipped Portable VHF-FM Radios
Time / Dates: 09:30 a.m. Monday, December 7, 2009
Location: RTCM HQ, Arlington, VA
1 Call to order, introduction of attendees, and approval of agenda
Mr. Hoffman called the meeting to order. The agenda was approved as written. The following persons were in attendance.
Chris Hoffman / . ACR Electronics / +44-1489880326 /Doug Ritter / Equipped to Survive Foundation / +1 480 598-1501 /
Masaaki Takahashi / Icom / +1 425 450-6043 /
Bob Markle / RTCM / +1 703 527-2000
fax: +1 703 351-9932 /
Jon Suehiro / Uniden / +1 817-858-3381 /
George E. Lariviere / Whiffletree Corp., Inc. / +1 207 647-3300
+1 207 647-3700 /
2 Approval of summary record of previous meeting (paper 235-2009-SC101-240)
The Summary Record was approved as written.
3 Status of ITU-R M.493-13
ITU-R M.493-13 was published in October a summary detailing the DSC call requirements for Class D Fixed and Handheld’s was presented (Paper 248-2009-SC101-242). However, there appear to be mistakes in the functions for handheld Class D’s. The final version does not agree with the draft version. Mr. Hoffman has asked Mr. Kim Fisher to look into this.
4 Review of relevant documents
Telenor ASA has proposed an MMSI scheme for unique handheld VHF DSC radios that would provide 100,000 MMSIs per MID (Paper 233-2009-SC101-239). This was considered by ITU Working Party 5B which will send a liaison statement to IMO COMSAR 14.
All of the other papers are comments, which were considered under agenda item 5. (Paper 196-2009-SC101-238 – most points are covered in the draft standard. Paper 253-2009-SC101-243 – will attempt to pick up in the standard. Paper 254-2009-SC101-244 – We accept that two receivers are needed for the SOLAS Class 3 radio, but one or two receivers should be allowed for others.)
5 Review and revision of draft standard
It was agreed that we intend to allow either one or two receiver designs for Class 1 and 2.
The following characteristics were agreed when no signal was being received or transmitted:
Class 3 has 2 receivers
· Ch 70 Rx on all of the time – must receive all DSC calls (radio always on or rapid switching)
· Other Rx can sleep – wake up every 2 sec or so for as long as it takes to detect a signal on Ch16 as a minimum
Class 1/2 with one receiver
· Must Rx all DSC distress calls
· Must monitor Ch 16 and Ch 70 for as long as it takes to detect a signal, every 2 sec (Ch 70 distress call is about 640 ms repeated 5 times, totaling just over 3 s.)
· Can sleep other times
Class 1/2 with two receivers
· Minimum requirement same as with one receiver, manufacturers can optionally implement the Class 3 scheme above.
The following characteristics were agreed when a signal was being received:
If Rx on Ch 70, then stop current process to get message, then carry on.
If Rx on voice channel with 2 Rx: Still monitor Ch 70 on second receiver
If Rx on voice channel with only 1 Rx, must still listen to channel 70 – i.e. interrupt voice channel once every 2 sec to listen on Ch70 as a minimum.
Any other scanning or dual watch functions (other than Ch70) cease while a signal is being received.
When a signal is being transmitted all radios (with either 1 Rx or 2 Rx) cease to listen, there is no requirement for radios with 2 Rx to have two antennas, one for each Rx.
Manufacturers can do more if they want to.
The battery duty cycle was discussed in some parts of the draft standard it is quoted as 10/10/80 and in others 5/5/90 (it should be the later). Mr. Hoffman will check through the standard and correct where necessary.
There was a discussion on the environmental test standards drawn from the ETSI Class D standard and IEC 60945. Although these would be required by definition for Class 3 SOLAS radios, it was suggested that other standards might be appropriate for Classes 1 and 2. Mr. Hoffman indicated that other equivalent standards (ETSI, JIS, etc.) should be acceptable. He also noted that the draft was drawn from the equivalent ETSI standard, so that radios sold in Europe should already be meeting these requirements. Manufacturers should suggest alternative requirements for Class 1 and Class 2 radios if they feel that the environmental tests in the present draft are not appropriate.
As with the environmental tests, the transmitter and receiver test requirements in sections 8 and 9 of the draft standard should be reviewed and revisions suggested before the next meeting.
Having added a second receiver to the standard the appropriate tests now need to be added to the Receiver Testing section of the standard.
6 Based upon discussions under agenda items 4 and 5; development of the future work plan for SC101/SC110.
We will try to complete the draft standard sometime in January and send it to all to review prior to the next meeting, with a view toward finalizing at the next meeting, and then circulate for vote.
7 Other business
There was no other business discussed.
8 Assignment of Action Items for next meeting
Mr. Hoffman will check on needed corrections to ITU 493-13. For instance, the published version in Table 4.4 shows that the handheld radio needs to transmit a distress relay acknowledgement. That is not consistent with the draft.
Manufacturers are asked to review the environmental test requirements, transmitter requirements and receiver requirements for all classes, and comment if necessary.
Mr. Hoffman and Mr. Markle will confirm with the FCC that manufacturer testing would be sufficient for authorization (outside laboratory tests not required).
Mr. Hoffman will update the standard, rewriting the watchkeeping and scanning sections based on discussions.
9 Date and Venue for next meeting
The next meeting will be on Friday, February 19, 2010 at 9:30 am at the RTCM offices in Arlington.
2