The 2.4G PCB Internal Patch Antenna paired with a 1.37 Coaxial Cable is a specialized, high-performance solution for embedding wireless connectivity into modern electronic devices. This assembly is engineered for applications operating within the 2.4 GHz ISM band (2400-2500 MHz), making it ideal for Wi-Fi (802.11 b/g/n) and Bluetooth/BLE (Bluetooth Low Energy) devices where space is a critical constraint.
This system offers a balance between compact size and reliable RF performance, often chosen over wire antennas or simpler chip antennas due to its optimized efficiency and repeatability.
1. The PCB Patch Antenna Element
The antenna itself is a patch or planar inverted-F antenna (PIFA) structure etched directly onto a small piece of Printed Circuit Board (PCB) material.
Compact & Tuned Design: PCB antennas are designed for precise impedance matching (typically 50 Ω and high efficiency within a compact footprint.2 They are engineered to specific dimensions to resonate optimally at 2.4GHz
Performance: They generally offer moderate gain (often 2 dBi to 4 dBi) and reliable, consistent performance in mass production, unlike less predictable hand-tuned elements.
Integration: The rigid PCB format is easily mounted within a device enclosure, usually via adhesive backing, requiring a specific "keep-out" area free of metal to function correctly.
2. The 1.37 Coaxial Cable
This refers to the thin, flexible cable connecting the PCB antenna to the device's radio module.
Diameter and Flexibility: The 1.37mm diameter cable offers a slightly larger, and often more mechanically robust, alternative to the popular 1.13mm cable. This slight increase in size can sometimes reduce insertion loss (attenuation) per meter.
Routing: The cable remains highly flexible, allowing for easy routing and strain relief within complex, space-constrained enclosures like wearable devices, handheld scanners, or smart sensors.
Loss Management: As with all thin coaxial cables, the length must be kept as short as possible to minimize signal loss before the RF signal reaches the radio transceiver.
3. Connector (MHF/U.FL Compatibility)
While the specific connector type is not listed, these assemblies almost universally terminate in an ultra-miniature coaxial connector from the MHF family, most often the U.FL (or IPEX/IPX) standard.
Miniaturization: These snap-lock connectors are tiny, consuming minimal space on the device's main circuit board, which is crucial for modern, small-form-factor designs.
Secure Connection: The snap-lock mechanism provides a reliable, secure connection resistant to minor vibrations, ensuring that the antenna remains connected even in portable or rugged devices.
Typical Usage Scenarios and Applications
The high efficiency and small footprint of the PCB patch antenna make it an essential component for products where aesthetics and internal space are prioritized.
Wearable Technology: Smartwatches, fitness trackers, and specialized medical patches rely on this form factor for reliable Bluetooth and Wi-Fi connectivity without having bulky external elements.
Smart Home Devices: Embedded within doorbells, thermostats, small security cameras, and hubs where an external antenna would compromise the device's design aesthetic.
Industrial Scanners and Handheld Terminals: Provides the necessary robust connectivity for inventory scanners, mobile point-of-sale (POS) systems, and field service tools that require internal antennas.
Small Form Factor Computers: Used in mini-PCs, single-board computers (SBCs), and custom computing modules that utilize a U.FL connector for an external antenna port.
Design Integration Best Practices
Optimal performance from an internal PCB antenna depends heavily on careful mechanical and RF design:
Keep-Out Zone: The antenna requires a defined clearance area around the radiating element (usually 5mmto 10mmthat must be entirely free of metal, ground planes, batteries, and display elements. Placing the antenna near metal will severely detune it and degrade performance.
Cable Management: The 1.37 cable should be routed away from noisy digital lines, switching power supplies, and high-speed data buses to prevent coupling electromagnetic interference (EMI) onto the sensitive RF signal.
Impedance Matching: The final assembled device enclosure and internal components can slightly shift the antenna's operating frequency. For best results, engineers often perform final impedance matching using small passive components (capacitors and inductors) on the main PCB to ensure the system remains at the desired 50Ω impedance.
The 2.4G PCB antenna with a 1.37 cable offers a robust solution for developers seeking a reliable, embedded antenna that minimizes product size while maximizing wireless performance in the universally important 2.4GHzband.
