Quantization is an important operation in digital communications systems. Quantizer not only introduces quantization noise but it also changes the statistical properties of the quantized signal. Furthermore, quantization noise cannot be always considered as an additive source of Gaussian noise. It depends on the input signal probability density function. In an orthogonal-frequency- division-multiplexing transmission the signal undergoes different operations which change its statistical properties. In this paper we theoretically analyze the statistical transformations of the signal from the transmitter to the receiver and determine how these effect the quantization. The discussed process enables the design of a quantizer with an optimal resolution for the required performance metrics. Simulations relate the effect of quantizer resolution and the channel statistics to the bit error rate at the receiver.