1. A wireless communication system, comprising: a receiving device that receives a wireless signal including a packet preamble structure having a partially periodic training component; and a frequency estimator that computes a plurality of component frequency estimates according to portions of the partially periodic training component, that aggregates the plurality of component frequency estimates to determine an overall frequency estimate for the received wireless signal, and that adjusts the receiving device according to the overall frequency estimate; wherein the frequency estimator computes at least one of the plurality of component frequency estimates by using portions of a guard interval (GI) from the partially periodic training component; wherein the frequency estimator computes at least one of the plurality of component frequency estimates by using phase data associated with a preliminary coarse frequency estimation using a short training field (STF); wherein the partially periodic training component is a long training field (LTF) consisting of four symbols; wherein the four symbols comprise two symbols that are together constituted of a double guard interval (DGI) and a pair of long training sequences (PLTS) and two symbols that are each constituted of a single guard interval (GI) followed by a long training sequence (LTS); wherein the frequency estimator computes the plurality of component frequency estimates based on phase detector outputs for varying combinations of the long training sequences (LTS); wherein a first frequency estimate of the plurality of component frequency estimates includes a phase detector output using the pair of long training sequences (PLTS) in addition to a phase detector output of the STF used in the preliminary coarse frequency estimation.