Introduction
Over 200 sorting carts running at high speed on an 800-meter loop — any single cart losing connection can cause mis-sorts and induction station backlog. This is the real pressure sorting centers face during e-commerce peak seasons. Traditional wireless solutions struggle with dense steel frames and strong EMI — signal bars may show full, but packet loss and latency are rampant, with carts frequently losing connection.
This case comes from a sorting center processing over 500,000 parcels daily. With KAXA’s integrated “leaky cable + industrial AP + onboard client” solution, we helped them achieve 200+ carts running simultaneously with zero packet loss and 6 months of zero communication failures.
Background
A large logistics sorting center in China spans approximately 50,000 square meters, featuring a cross-belt sorting system with 800 meters of total sorting line, 6 sorting lines, and over 500,000 parcels processed daily. The system includes 60 induction stations and 200+ mobile sorting carts. Induction stations must transmit parcel destination, weight, and dimension data to the control system in real-time, while mobile sorting carts operate at high speed on the 800-meter loop — receiving dispatch commands and uploading position/status data in real-time. Any communication interruption can result in mis-sorts, induction station backlog, or even complete line shutdown.
Challenges
1. Dense Metal Obstruction: Dense steel frames and multiple curves on the loop severely attenuated wireless signals. Traditional solutions created frequent blind spots — full signal bars often masked actual packet loss and latency.
2. High-Speed Roaming Dropouts: 200+ carts operating at high speed on the 800-meter loop required frequent AP handovers. Traditional solutions suffered long handover times, causing frequent dropouts and lost dispatch commands.
3. Strong EMI: Dense VFDs, motors, and other high-power equipment generated intense electromagnetic noise. The 2.4GHz band was severely congested, and conventional wireless solutions lacked anti-interference capability, resulting in significant data jitter.
4. Peak Capacity Bottleneck: During e-commerce peak seasons, instantaneous concurrent data traffic surged, causing network congestion, data backlogs, and carts losing connection — severely impacting efficiency.
Solution
KAXA deployed an integrated “leaky cable + industrial AP + onboard client” wireless solution for the cross-belt sorter:
1. Full-Coverage — Leaky Cable Creates a “Blind-Spot-Free Signal Corridor”
KX-CABLE-50-12 leaky cable was installed along the cross-belt sorter loop, replacing traditional point-source antennas. Through precision-slotted design, the cable provides uniform, directional signal radiation along the entire track — forming a consistent “wireless corridor” that ensures identical signal strength at any position, fundamentally eliminating blind spots at curves and dead zones. A single AP supports up to 2 sections of leaky cable (each up to 100 meters), perfectly suited for short-distance lines.
2. High-Reliability Access — KXA3100-5N Industrial Wireless APs
KXA3100-5N APs were deployed at key points along the line, paired with leaky cable for full-area signal coverage. The APs support 4900MHz~6100MHz ultra-wide frequency band and DFS, automatically avoiding 2.4GHz EMI to ensure stable data transmission.
For sorting lines exceeding 200 meters, multiple APs were deployed in segmented coverage, combined with KAXA’s proprietary fast roaming technology to achieve automatic smooth handovers within 50ms, ensuring carts experience zero interruption as they move between coverage zones.
3. Onboard Terminals — KXC1100-5N Industrial Wireless Bridges (Critical)
Each cross-belt sorting cart is equipped with a KXC1100-5N industrial bridge as an access layer terminal, connecting directly to the AP via leaky cable signal. Supporting fast roaming protocols (IEEE 802.11r), the bridge automatically switches to the adjacent AP within milliseconds when the current AP signal weakens — achieving “imperceptible roaming.”
Supporting 4900MHz~6100MHz ultra-wide band and DFS, the bridge’s strong anti-interference capability ensures uninterrupted communication during high-speed cart operation, even in the most electrically noisy environments.
4. Wired Backbone — KXS208G Industrial Switches
KXS208G switches were deployed in the control room and at sorting line zones to connect fixed equipment (induction stations, PLCs, HMIs, sorting chute sensors), forming a “wired backbone + wireless extension” hybrid architecture with the wireless portion.
Redundant ring network design provides automatic failover within 50ms to backup links, ensuring critical data continuity. Time synchronization accuracy is controlled within ±1μs, ensuring collaboration between PDA scanning and robotic arms with <1ms error — critical for high-speed accuracy.
Results
- 200+ sorting carts achieved cross-AP roaming ≤ 50ms with zero packet loss and zero dropouts throughout operation — maintaining zero downtime even during peak e-commerce seasons.
- Blind-spot-free coverage: Leaky cable installed along the entire track, eliminating dead zones at curves and corners.
- Low latency and high reliability: Data transmission latency < 20ms with near-zero packet loss — commands reach carts instantly, enabling precise sorting at full speed.
- System achieved 6 months of zero communication failures with sorting efficiency improved by 25% — directly translating to higher throughput during peak periods.
Customer Testimonial
“Our sorters used to crash frequently during peak seasons. After switching to KAXA’s wireless + leaky cable solution, we haven’t had a single communication failure in 6 months. Over 200 carts run smoothly, and the efficiency improvement has been remarkable.”
