import pandas as pd


def process_small_bts_data(file_path: str):
    dfs = pd.read_excel(
        file_path,
        sheet_name=["BTS"],
        engine="calamine",
        skiprows=[0],
    )
    df_bts = dfs["BTS"]
    df_bts.columns = df_bts.columns.str.replace(r"[ ]", "", regex=True)
    df_bts["code"] = df_bts["name"].str.split("_").str[0]
    df_bts["code"] = (
        pd.to_numeric(df_bts["code"], errors="coerce").fillna(0).astype(int)
    )
    df_bts["ID_BTS"] = df_bts[["BSC", "BCF", "BTS"]].astype(str).apply("_".join, axis=1)
    df_bts["ID_MAL"] = df_bts[["BSC", "BTS"]].astype(str).apply("_".join, axis=1)
    df_bts = df_bts[["ID_BTS", "ID_MAL", "code", "name"]]

    return df_bts