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[LevelII #TJW-252571]: DATA LEVEL II NEXRAD at DENVER

> Dear Jeff:
> 
> Many thanks for your fast reply.
> I'm really impressed by your high quality level response. CONGRATULATIONS.
> 
> Please let me know if these links to the files are permanent or temporary.
> If they are permanent I will copy to my local hard drive the data as I will 
> need (3 radars for this period at Level II data is quite an amount of data 
> for the beginning). If they are temporary I will copy all and allow you to 
> remove the links.
> 
> Thank you also for the Level III data. They will be of extremely help to 
> compare my results against and be sure I am not making any mistake in the 
> Level II data manipulation.
> 
> Thank you for the link to the documentation.
> Unfortunately I have already explored this site and I didn't find help on 
> them.
> 
> My doubts are for instance:
> 
> 1) Dimensions and differences between the values SPULSE and  LPULSE of the 
> file header and the value PULSE_WIDTH in the RAY headers.
> I have found in some spec documentation that the nominal pulse width is 1.57 
> µs (short pulse); 4.5 µs (long pulse) ± 4% Are SPULSE and LPULSE the real 
> pulse duration (in miliseconds???) for short and long pulses?
> Is there any header specifying which is used in a particular volume (rule for 
> using short or long)?

These informations are contained in the message type 18, and not in our 
netcdf-Java reader. The document should have very detail description.
> 
> 2) These SPULSE and LPULSE values seems to be in contradiction with the  
> PULSE_WIDTH recorded for any ray and any sweep (in miliseconds????).
> Which is the real value used for the volume measurements?
> 
> 2) The beam width that appears in the headers (0.5 degrees for the super 
> resolution sweeps and 1.0 degrees for the rest) are nominal or the true 
> values?
> I have seen in some NEXRAD documentation that the real one-way 3 dB beam 
> width is 0.96° at 2.7 GHz and 0.88° at 3.0 GHz, so none of the header values 
> are true?
> 

0.5 degree and 1.0 degree are the azimuth difference, not the beam width.


Yuan
> 3) In the super resolution mode, they are really using a beam width of 0.5° , 
> as the headers suggest, or this just means that the azimuth sector of these 
> rays is 0.5° (but not the real beam width)?
> (how the beam width can vary if the antenna and the frequency are the same 
> for the different sweeps?).
> 
> I'm not sure if you, or your internal staff that write radar readers, can 
> help me with that doubts (the documents on the mentioned webpage didn't 
> helped, or I was unable to use them conveniently).
> But in any case if you can guide me to contact some expert people that could 
> solve these doubts I will be extremely grateful.
> 
> Again many thanks for your extraordinary response and for your help.
> 
> Warm regards
> 
> Daniel
> 
> 
> 
> 
>  

Ticket Details
===================
Ticket ID: TJW-252571
Department: Support IDV
Priority: High
Status: Open