Antenna and feeder system: the "blood vessels" and precise testing methods of wireless communication
In the vast network of modern wireless communication, antenna and feeder systems are like the "blood vessels" and "voice organs" of the human body. Although they are not often directly perceived, they bear the heavy responsibility of signal transmission. The antenna and feeder system, a complete link consisting of antennas, feeders (coaxial cables or waveguides), connectors, lightning arresters, and tower releases and combiners that may be included, constitutes the physical channel for base station signal transmission and reception. Its performance directly determines the communication quality, coverage and network reliability.
Core uses of antenna and feeder systems
1. Signal radiation and reception: The antenna is the "throat" of the system, responsible for converting the high-frequency current generated by the transmitter into electromagnetic waves to radiate into space (transmission process), or converting electromagnetic waves in space into high-frequency current and sending them to the receiver (reception process).
2. Efficient signal transmission: The feeder is like a "blood vessel", and its core task is to transmit RF energy between the antenna and the transceiver with minimal loss and distortion. High-quality feeders can effectively reduce the attenuation of signals during transmission.
3. System protection: Lightning arresters and other components are the "immune barriers" of the system, protecting expensive transceiver equipment from damage caused by overvoltages such as lightning surges.
4. Signal enhancement and management: Tower-mounted amplifiers (TAA) and other devices are like "energy boosters" that can compensate for feeder losses and improve uplink reception sensitivity; combiners/splitters are used to achieve multi-band, multi-system signal sharing antennas and optimize site resources.
Key factors affecting the performance of antenna feeder systems
The performance of antenna feeder systems is not static, and many factors can cause them to deviate from the ideal state:
Connector problems: Loose interfaces, oxidation, water ingress, poor soldering or improper installation will lead to severe signal reflection (deterioration of standing wave ratio) and increased insertion loss, which is one of the most common fault points.
Feeder damage: Cable sheath damage, extrusion deformation, excessive bending (less than the minimum bending radius), internal water ingress or aging will significantly increase transmission loss and affect signal strength.
Antenna aging/displacement: Antenna vibrator rust, physical deformation, and deviation due to strong wind or looseness will directly affect the radiation pattern, gain, and coverage expectations.
Environmental erosion: Long-term exposure to harsh environments such as ultraviolet rays, high temperature, high humidity, and salt spray will accelerate the aging of cables and connectors and performance degradation.
External interference: Strong electromagnetic radiation sources nearby may interfere with the feeder system and affect signal purity.
Accurate diagnosis: the core value of antenna and feeder line testing and the application of TFN 100L
It is precisely because of the above factors that antenna and feeder line testing is crucial from engineering installation, daily maintenance to troubleshooting. It can quickly diagnose the system status, locate hidden dangers, and ensure efficient and stable operation of the network. Professional instruments are the cornerstone of this work, such as the TFN 100L series antenna and feeder line tester.
TFN 100L: A powerful tool for cable antenna analysis
The TFN 100L cable antenna analyzers are designed for field engineers and integrate a number of key test functions:
1. Standing wave ratio/return loss test: One of the core items of antenna and feeder line testing. TFN 100L can quickly measure the reflection of each point in the system (especially the connector). High standing wave ratio means serious impedance mismatch, and a large amount of signal is reflected back to the device, which not only reduces the transmission efficiency, but also may damage the transmitter power amplifier in long-term operation. The instrument displays the results intuitively, helping engineers to immediately determine whether the interface is good and whether the antenna is damaged.
2. Insertion loss/cable loss test: Directly measure the power attenuation value of the signal after passing through the entire feeder or specific components (such as jumpers, lightning arresters). TFN 100L cable antenna tester provides accurate readings, which engineers can use to determine whether the feeder length exceeds the standard, whether the cable quality is qualified, and whether the connector loss is abnormal.
3. Fault location (DTF): TFN 100L's "radar" function. It sends test signals along the feeder and accurately measures the time and strength of the reflected signal, and graphically displays the location and nature of the fault point (such as open circuit, short circuit, water immersion, extrusion deformation) on the screen. This greatly shortens the troubleshooting time, especially when working in high altitude or hidden locations such as tower tops.
4. One-button automated testing: For common test items, TFN 100L provides a convenient one-button operation mode to simplify the process, improve on-site work efficiency, and reduce human operation errors.
5. Rugged, durable and long battery life: Designed for harsh outdoor environments, it has good protection performance and long battery life to ensure all-weather operation needs.
Workflow of efficient antenna and feeder testing (combined with TFN 100L):
1. Connection preparation: Disconnect the antenna and feeder under test from the base station equipment, and connect TFN 100L to the port to be tested through a high-quality test jumper.
2. Parameter setting: Select or enter key parameters such as the operating frequency range of the system under test and the feeder type (affecting the propagation velocity factor VP) in the instrument.
3. Key indicator test:
Perform VSWR/return loss test: Quickly scan the operating frequency band to confirm whether the overall matching performance meets the standard and identify abnormal points within the band.
Perform insertion loss test: Measure the actual loss value of the entire feeder or key components and compare it with the theoretical value or historical data.
4. In-depth diagnosis - DTF test: Start the fault location function. TFN 100L will present a "waveform diagram" of the entire feeder. Engineers need to interpret the graph:
Distance judgment: The instrument scale clearly indicates the physical distance between the fault point and the test port.
Fault type identification: According to the characteristics of the reflection peak (size, positive and negative), determine whether it is an open circuit (large positive peak), short circuit (large negative peak), slight mismatch (small peak) or water immersion/deformation (abnormally wide peak).
5. Result analysis and processing: Based on the test results, identify the problem points (such as loose connectors at a certain distance, suspected damage to a certain section of feeder), and formulate a repair or replacement plan. After the test is completed, save the records for subsequent tracking and comparison.
Conclusion
The antenna and feeder system is the cornerstone of the wireless communication network, and its performance is directly related to user experience and operating costs. A deep understanding of its composition, function and key factors affecting its stability is the premise for ensuring network quality. The use of advanced antenna and feeder test instruments such as the TFN 100L series for standardized and accurate measurement and diagnosis is a necessary means to achieve efficient maintenance, rapid troubleshooting, and ensure long-term stable and reliable operation of the network. Regular antenna and feeder testing is like a "health check" for the communication network, which is an indispensable part of preventing major failures and optimizing network performance. As 5G networks are being deployed in depth and the requirements for antenna and feeder systems are becoming increasingly stringent, professional and efficient antenna and feeder line testing practices are of greater strategic significance.