-
Why Is My RF Signal Weak After Adding a Filter?
May , 16 2026
At first glance, adding an RF filter sounds like a simple upgrade. The goal is usually clear: Reduce interference Clean up the signal Improve network stability Protect sensitive RF equipment But in real projects, many engineers and installers run into the same frustrating problem: “The interference is gone, but now the signal is much weaker.” This happens more often than people expect, especially ...
View more
-
How to Customize Frequency Bands for Multi-Operator POI Combiners?
May , 30 2026
In modern Indoor Building Solutions (IBS) and Distributed Antenna System (DAS) projects, multi-operator co-construction and infrastructure sharing have become the definitive global model. Whether navigating international airports, expansive subway networks, high-density commercial complexes, mega-stadiums, or premier corporate high-rises, mobile operators increasingly prefer to deliver seamless wi...
View more
-
Low PIM Components: The Real Engineering Math From link budget to selection traps
Jun , 16 2026
Anyone who has worked on distributed antenna systems will eventually have a head‑on fight with PIM. This post skips the fluff and only shows the engineering math. 1. Where PIM comes from — the formula Two frequencies f1, f2 pass through a non‑linear node (loose connector, oxidized plating, magnetic material) and generate intermodulation products: 3rd order: 2f1－f2 , 2f2－f1 5th order: 3f1－2f2 , 3f2...
View more
-
Why Can’t a Power Divider Replace a Tapper in Indoor DAS?
Jun , 23 2026
Anyone who has worked on in‑building DAS eventually hits this problem: the main line signal is strong, but by the time it reaches the far‑end antenna port, there's almost nothing left. If you split it with power dividers all the way, each split makes it weaker, and the far end can't even get a phone registered. Then someone tells you — use a tapper. But what exactly is a tapper? How is it differen...
View more
-
What Makes a Tapper Indispensable for Long-Distance Indoor Coverage?
Jun , 30 2026
Anyone who has designed or deployed a Distributed Antenna System for a tunnel, a subway, or a 200‑meter office corridor knows this problem: the signal at the head‑end is strong, but by the time it reaches the far end, there's barely enough to keep a call connected. You can crank up the source power. You can add line amplifiers. But at some point, the physics of coaxial cable catches up with you. A...
View more
-
PIM Interference vs. External Interference: How to Quickly Tell Them Apart On‑Site?
Jul , 07 2026
Anyone who does base‑station maintenance or network optimisation eventually runs into this: uplink noise floor spikes, users complain about dropped calls and low throughput, yet VSWR tests pass and there are no equipment alarms. Where is the problem? At this point, you have two possible culprits – PIM (passive intermodulation) interference generated inside your own system, or external RF interfere...
View more
