Legal Question in Civil Litigation in California

The citation is perfectly valid. All that's missing is your agreement that you received it. The officer's testimony that he handed it to you will prove the point even though you didn't acknowledge it. And if you're smart, you won't deny under penalty of perjury that he gave it to you.

Whether you have to pay depends upon whether you're guilty and whether you can persuade a judge or jury that there is a reasonable doubt of your guilt. You have not provided enough information to answer those questions.

If you ignore the citation, you will have an arrest warrant issued against you, signature or not. If instead you go to court and argue the signature, and your actual defenses, you will have a better outcome -- the judge will decide on the merits without being 'annoyed' with you having ignored the citation and the authority of the court.