double max_bw=bandwidth.peak;
double min_bw=bandwidth.peak-(wifi_max_rate_-wifi_min_rate_);
double model_rate=bandwidth.peak-(wifi_max_rate_-model_rate_);
double max_bw=bandwidth.peak;
double min_bw=bandwidth.peak-(wifi_max_rate_-wifi_min_rate_);
double model_rate=bandwidth.peak-(wifi_max_rate_-model_rate_);