05.053GPPRadio transmission and receptionTS
The reference configuration for the radio subsystem is described in 3GPP TS 05.01.
The micro‑BTS is different from a normal BTS in two ways. Firstly, the range requirements are much reduced whilst the close proximity requirements are more stringent. Secondly, the micro‑BTS is required to be small and cheap to allow external street deployment in large numbers. Because of these differences the micro‑BTS needs a different set of RF parameters to be specified. Where the RF parameters are not different for the micro‑BTS the normal BTS parameters shall apply.
The pico-BTS is an extension of the micro-BTS concept to the indoor environments. The very low delay spread, low speed, and small cell sizes give rise to a need for a different set of RF parameters to be specified.