Basic Japanese requirements

Hi, is it necessary to have knowledge of at least some words in Japanese (written / spoken) when visiting? Or can one survive well for a few weeks by just speaking English? Thanks! 

I think you'll be able to survive a few weeks with only English, but there may be a few words that you might want to know. For example thank you in Japanese is "arigato gozaimasu ". Or "sumimasen " which means excuse me also comes in handy, when trying to ask somebody something.  If you can remember the Japanese character 駅  which means station,  it could help you get around. Hope this helps!