As others have said; The Forever War, by Joe Haldeman.
Tongue controls (Chapter 7 and 13);
All I could hear was Potter's breathing and the soft crunch-crunch of my boots.
Couldn't see much of anything, so I tongued the image converter up to a log two
intensification. That made the image kind of blurry but adequately bright.
I shuffled over to my place on the perimeter to watch for god knows what...
but I was so weary I couldn't keep my eyes open. Finally I tongued a stimtab,
knowing I'd pay for it later.
Low Tech warfare (Chapter 34);
Inside, I could see the rocket that had missed me drifting lazily through the
gloom, rising slightly as it passed through to the other side of the dome. It
would vaporize the instant it came out the other side, since all of the kinetic
energy it had lost in abruptly slowing down to 16.3 meters per second would
come back in the form of heat.
Nine people were lying dead, facedown just inside of the field’s edge. It
wasn’t unexpected, though it wasn’t the sort of thing you were supposed to tell
Their fighting suits were intact—otherwise they wouldn’t have made it this far,
but sometime during the past few minutes’ rough-and-tumble, they had damaged
the coating of special insulation that protected them from the stasis field.
So as soon as they entered the field, all electrical activity in their bodies
ceased, which killed them instantly. Also, since no molecule in their bodies
could move faster than 16.3 meters per second, they instantly froze solid,
their body temperature stabilized at a cool 0.426 degrees Absolute.
I arranged the archers in a circle around the fighter (its landing fins would
give them partial protection from missiles coming in from behind) and between
each pair of archers put four other people: two spear-throwers, one
quarterstaff, and a person armed with a battle-ax and a dozen throwing knives.
This arrangement would theoretically take care of the enemy at any range, from
the edge of the field to hand-to-hand combat.
... even if you're not sure, read it anyway.
It's one of the best SF books ever written, winning the Hugo, Nebula, and Locus awards for Best Novel.