Original sentence: -174dBm represents the noise power due to KTB watts where B = bandwidth in Hz, T is the system temperature in kelvin and K is Boltzmann's constant (1.38 x10−23 joules per kelvin = -228dBW/K/Hz)
Edited sentence: -174dBm represents the noise power due to KTB watts where B = bandwidth in Hertz (Hz), T is the system temperature in kelvin and K is Boltzmann's constant (1.38 x10−23 joules per kelvin = -228dBW/K/Hz)