1. Technical Field
This invention relates to the use of transmission line testing equipment used for the site testing of wireless transmission systems at the tower site. A variety of transmission line problems can occur at the transmission tower site which can create, for example, wireless phone users symptoms such as poor receiver signals and increase drop out call rates. Such problems can occur in a variety of situations such a rainwater penetration, condensation, and bullet holes, for example. Also improper installation situations such as feed line clamps being over tightened or for example, crimped or smashed cable and improper or loose connections during installation, etc.
Determining the nature and most importantly the location of the problem along the transmission line is critical to the proper repair and replacement of the affected element in the field.
2. Description of Prior Art
Prior art testing analysis devices have been developed to test transmission lines and analyze antennas used in the cellular telephone industry. Typically, such testing devices will determine the nature of the problem and attempt to isolate and thus indicate the location of the problem within the system. Such testing equipment utilizes a variety of specific testing procedures such as frequency domain reflectometer (FDR) to cover the required frequencies or range of frequencies. Time domain reflectomoter (TDR) test instrument uses a pulse which is able to detect system faults that may lead to a system failure. Other tests will perform a variety of RF measurements such as return loss and SWR measurements, well known and understood by those within the art.
Such test as return loss, cable loss and distant to fault can be performed by such testing equipment. Specific samples of testing equipment are manufactured by Anritsu under the brand name such as Site Master, Model Series 51134 and 5331-2C. It is important to note that with the use of the existing testing equipment, it is very difficult to determine the exact physical location of the problem in the transmission line given that often the actual feed line length is not known to the technician at the location. Present testing equipment may indicate a problem at some point along the feed line and antenna, but often does not relate physically where that problem i.e. fault is actually located.
A multi-feature testing device for use on wireless transmission towers that can induce a number of testing criteria or faults to the cell tower transmission circuit. The device has multiple testing features including an open short, a short induced by grounding and interchangeable loads and connectors. The induced loads can be selectively changed by the use of interchangeable load circuits, well known and available within the art. An interchangeable connector is provided to accommodate a variety of connector configurations encountered in the field. The testing device allows a technician to easily perform multiple fault location tests at selective locations on the tower to isolate the fault area so that associated testing equipment can determine the nature and the exact location of the problem within the section isolated.