Why Do Phones and Tablets Keep Losing Signal or Wi-Fi?

Why Signal Drops Are Not an Antenna Problem

Users often blame antennas, RF chips, or firmware when smartphones or tablets suffer from unstable 5G signals or frequent Wi-Fi disconnections. However, field data reveals a less visible but far more critical root cause: grounding failure in EMI shielding interfaces.

Based on an internal analysis of 137 EMI-related complaints in 2023 from global Tier-1 consumer electronics brands:

• 72% of “unstable 5G signal” cases were traced to elevated contact resistance at PCB grounding points

• 68% of repeated Wi-Fi dropouts were caused by poor grounding between shielding enclosures and the mainboard

• Most failures appeared 2–3 months after mass production, when products were already on the market—making remediation extremely costly

In high-frequency systems (>3 GHz), such as 5G and Wi-Fi 6E, even minor grounding degradation has major consequences. According to the IEEE EMC Society, every 0.01 Ω increase in grounding impedance can reduce shielding effectiveness by 3–5 dB.

For a deeper understanding of how conductive foam works in EMI grounding, see
Working Principle and Core Advantages of Conductive Foam:
https://www.konlidainc.com/workin.html

Why Traditional Grounding Solutions Fail in Thin Devices

As consumer electronics become thinner and more integrated, many conventional grounding methods reach their performance limits.

Real-world case (anonymized):
A flagship TWS earbud failed EMC testing after storage in high temperature and humidity. Delamination between the release liner and standard conductive foam caused grounding loss, resulting in losses exceeding RMB 28 million.

This type of failure mechanism is further analyzed in
Conductive Foam Failure Analysis: From Root Causes to Permanent Solutions:
https://www.konlidainc.com/article/failure.html

Konlida’s Answer: SMT Gasket for High-Frequency Grounding

Konlida does not pursue “one-size-fits-all” materials. Our SMT conductive foam gaskets are specifically engineered for high-frequency, ultra-thin, and high-reliability consumer electronics.

Three Layers of Reliability

Structural Reliability

• Tin-plated PI film (25 ± 1 µm) with high-purity silicone foam core

• Withstands three lead-free reflow cycles at 260 °C without delamination

Electrical Stability

• Surface resistance ≤ 0.03 Ω/sq (ASTM F390)

• Contact resistance < 0.05 Ω after 30% compression (measured)

Mechanical Durability

• Compression recovery > 92% (30%, 85 °C × 168 h)

• No performance degradation after 30 thermal shock cycles (-40 °C ↔ 125 °C)

Measured Performance Comparison

Source: Konlida Laboratory, Nov. 2024

These results highlight why SMT-compatible conductive foam has become the preferred EMI grounding solution in modern smartphones, tablets, and wearables. For SMT-specific design insights, refer to
SMT Gaskets: High-Precision EMI Shielding and Automation-Ready Solution:
https://www.konlidainc.com/gasket.html

Three Design Rules to Get EMI Grounding Right the First Time

Konlida has helped 37 consumer electronics models achieve zero EMI rework by enforcing the following principles:

1. Pad Size Matching
   Recommended pad width: 3.3 ± 0.1 mm
   Recommended pad length: 2.3 ± 0.1 mm
   Gap: 1.0 ± 0.1 mm

2. Compression Control
   Target compression: 25–30%
   Avoid >40% to prevent permanent set and resistance drift

3. Avoid Dynamic Stress Zones
   Do not place SMT conductive foam near hinges, snaps, or moving structures

Final Takeaway

If your smartphone or tablet suffers from intermittent signal loss, the root cause is often not RF design—but unstable grounding. In the 5G and Wi-Fi 6E era, SMT conductive foam gaskets provide a proven path to stable impedance control, consistent shielding effectiveness, and long-term product reliability.

Choosing the right grounding solution early is the difference between passing EMC once and fighting EMI failures after launch.