Autoname .PDF conversion to the name of the .xlsb from which it came

I have a macro (see code below) that automatically converts the print area of the a worksheet into a pdf file, and then automatically saves the PDF into a specified location, and finally saves the portion of the excel file that affected the print area.

Right now I have to specifically name "filename" whatever I want the PDF to be saved as. Since I have to replicate my workbook several times, it would be very convenient if the code could autoname the PDF with the same name as the .xlsb file from which it was made. For instance, if the excel file's name is "Doe, John.xlsb", then the code auto saves the PDf as "Doe,John.pdf" when that macro is clicked. This would save a tremendous amount of time of renaming "filename" for 80 people for 26 pay cycles (2080 times!).

ActiveSheet.ExportAsFixedFormat Type:=xlTypePDF, Filename:= _
        "G:\Timesheets\PDF Archive\FY2012\27 = 061712 - 063012\filename.pdf", _
        Quality:=xlQualityStandard, IncludeDocProperties:=True, IgnorePrintAreas _
        :=False, OpenAfterPublish:=False
    Range("A1:O1").Select
    ActiveWorkbook.Save