Wireless remote control for Nikon D3100 to auto-focus in video?

Okay, so I have a Nikon D3100 and have recently found that it's not possibly to auto-focus the camera without being behind it so that someone is able to push the shutter release button half-way down. Which is a problem for me. As I want to shoot a video of myself in front of the camera, and have the camera to auto-focus on me when I'm in front of the camera lens- which isn't possible as I can't push down the shutter button without behind behind the camera.
Anyway, I was wondering if it is possible to buy a wireless remote that will enable me to use auto-focus whilst I'm in front of the camera.

Sorry if this doesn't make much sense, I don't have much experience when it comes to shooting video.

The ML-L3 remote WILL allow the camera to focus while taking pictures but not video.

The D3100 will continuously auto focus in live view mode and while recording video. You have to put your D3100 in AF-F mode for it to continuously focus on you. You also have to set it to subject tracking in manual mode.

However your better off leaving the camera in manual focus mode while recording video so you don't hear the lens AF motor all the time.

Actually, the D3100 can't use the ML-L3 remote. The ML-L3 remote is a wireless remote, and the D3000 and D3200 can use this wireless remote, but the D3100 is wired remote only.

However, in my view, you have the better solution.

First and foremost, a wired remote is faster than an IR remote. I have direct knowledge of this as I have engineered camera trigger and intervalometer systems for both wired and IR triggers.

And a wired remote typically has a 2-level switch. Like the shutter, you can press a wired remote half-way down for focusing, and all the way down for the photo (however, I'm not sure if it will trigger video on the D3100 or not).IR remotes do not have this capability, which is one reason they have a delay, as cameras typically internally have a focus - delay - trigger action when you use a IR remote.

This means when the camera is triggered with a IR remote, it will first focus, then after a pre-determined delay, fire the trigger. This delay is part of the reason IR is slower, but also, the IR system sends out a specific encoded sequence via IR transmitter, which does take time.

And if you want a wireless remote, you can buy an inexpensive trigger, such as a Yongnuo RF-603, which is a RF, not IR trigger, and with a 100~200ft range.

And finally, there are virtually NO IR remote intervalometers - at least commercially made. They are all wired only. I have designed and built IR versions, but they are not available commercially.

The wired remote you need is a Nikon MC-DC2 or compatible 3rd party remote.

However, the easy solution is to simply pre-focus the lens in manual focus mode to where you will be standing. And you can stop the lens down a bit to add a bit of DoF so that if you do move around a bit, you will still be in focus. This will work unless you are walking all around the place, which in that case, you will want an assistant to handle the camera.