I worked for a city engineering department for 35 years and one of the things that I learned while there was how to trigger an induction-loop traffic signal. This is the type of traffic signal that uses wire loops placed in the pavement to sense vehicles and cause the signal to turn green for your lane. As you may know not every signal will pick up a motorcycle and those magnets that claim to do so are as worthless as a rabbit's foot. Even my GPR-S, with its big D&D sepex motor, will not trigger some signals - so you can forget magnetic fields, they won't do the job. What you need is real steel - like my Triumph's steel rims. But if your bike has aluminum rims you may have a problem.
I asked our signal maintenance division how they adjusted traffic signals and tested them. To my surprise, they adjust the sensitivity and check the operation of the signal detection system after fooling with it by throwing an old shovel on top of the loops. If the shovel triggers the signal then they are happy and move on to the next problem - such as replacing light bulbs.
So if you are all by yourself, the traffic signal is not sensing your motorcycle and you don't want to blow the red light, or perform a series of right turns on the red (where legal), here is what you can do: Deploy your side stand while you are stopped. If you can see the wire cuts in the pavement, attempt to place the foot of your side stand over one of the wires. If the wire loop cuts are not visible, hope for the best. This usually will work and beats running the red light. Just don't forget to retract your side stand before taking off.
Many traffic signals are being converted to a video system which will sense both motorcycles and bicycles - assuming that they are not malfunctioning. There are also new systems that use some sort of radio or microwaves that sense vehicles and also work for motorcycles and bicycles. These are usually used in the boondocks where electromagnetic interference is minimal. Due to the cost of replacing the induction loop wires when the pavement is overlaid with new asphalt, expect to see these alternative wireless detection systems become more common.