There are many existing transliteration systems for Arabic, among them SATTS (developed to allow for transmission of Arabic text over telegraphs), the Buckwalter system (developed by Tim Buckwalter), Arabic chat alphabets (used in electronic communications before Arabic script could be easily rendered on electronic devices like phones), and numerous others listed at https://en.wikipedia.org/wiki/Romanization_of_Arabic. There's also the Maltese alphabet, a Roman script used for Maltese (which is an Arabic language).
There are some linguistic oddities in the article, like this: "Emphatic Letters: These letters are pronounced from the back of the throat..." With the exception of heth (a voiceless pharyngeal fricative), the emphatic letters are actually pronounced with the tongue near the roof of the mouth (similar to English t, d, s etc.), but with a secondary articulation that varies across "dialects" (actually distinct Arabic languages). In some dialects the emphatics differ from the non-emphatics only in causing a slightly different articulation of the following vowel.
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