回答我的问题。
我分享我的解决方案，以防有人需要。
在app/code/core/Mage/Shipping/etc/system.xml中，将其添加到新运营商

<logo>
    <label>Logo</label>
    <frontend_type>image</frontend_type>
    <backend_model>adminhtml/system_config_backend_image</backend_model>
    <upload_dir config="system/filesystem/media" scope_info="0">freeshippingtimisoara/logo</upload_dir>
    <base_url type="media" scoope_info="0">freeshippingtimisoara/logo</base_url>
    <sort_order>3</sort_order>
    <show_in_default>1</show_in_default>
    <show_in_website>1</show_in_website>
    <show_in_store>1</show_in_store>
</logo>

在/app/code/core/Mage/Shipping/Model/Carrier的载体模型上添加此功能

public function getShipmentImageSrc($shipping)
{
    $logo = $this->getConfigData('logo');
    $imageFilepath = DS . $shipping . DS . $_code . 'logo' . DS . $logo;
    if( file_exists(Mage::getBaseDir('media').$imageFilepath) ){
        return Mage::getBaseUrl('media').$imageFilepath;
    }
    return false;
}

将/app/code/core/Mage/Checkout/Block/Onepage/Shipping/Method/Available.php克隆到本地并添加以下函数：

public function getCarrierLogo($carrierCode)
{
    if ($logo = Mage::getStoreConfig('carriers/'.$carrierCode.'/logo')) 
    {
        $carrierModel = Mage::getModel('shipping/carrier_' . $carrierCode);
        $logo = $carrierModel->getShipmentImageSrc($carrierCode);
        return $logo;
    }
    //$shippingModel = Mage::getModel('shipping/shipping');
    //$carrier = $shippingModel->getShipmentImageSrc($carrierCode);
    //Mage::helper('firephp')->debug( $carrier );
}

在app/design/frontend/default/sex/template/checkout/onepage/shipping_method/available.phtml中使用此文件我的模板中有此文件，如果您想更改，最好将其复制到您的模板中。

<?php if($this->getCarrierLogo($code)): ?>
    <span class="carrier-desc" style="margin:0 10px">
        <img src="<?php echo $this->getCarrierLogo($code) ?>" alt="<?php echo $_code; ?>" />
    </span>
<?php endif; ?>