The **ALR-041-R** is a high-performance active antenna module designed primarily for GNSS (Global Navigation Satellite System) applications. It is engineered to provide high gain and low noise for satellite signal reception, typically used in automotive and industrial tracking systems. --- ### 1. Key Technical Specifications The following table outlines the core electronic parameters of the ALR-041-R: | Parameter | Value / Specification | | :--- | :--- | | **Frequency Range** | 1575.42 MHz (GPS L1) / 1602 MHz (GLONASS) | | **Supply Voltage** | 2.5V to 5.0V DC | | **Gain (LNA)** | 28 dB (Typical) | | **Noise Figure** | 1.5 dB (Typical) | | **Output Impedance** | 50 Ohms | | **Current Consumption** | 10 mA to 15 mA | | **Connector Type** | Usually RF Coaxial (e.g., U.FL or SMA depending on variant) | --- ### 2. Electronic Component Breakdown The ALR-041-R is more than just a piece of metal; it is an "Active" antenna, meaning it contains integrated circuitry. #### A. The Ceramic Patch Element At the core is a ceramic patch antenna. The dimensions of this patch are tuned to the specific wavelength of GNSS signals. The ceramic material has a high dielectric constant, which allows the antenna to be physically small while maintaining efficiency. #### B. Low Noise Amplifier (LNA) Because satellite signals are extremely weak by the time they reach Earth (often below the thermal noise floor), the ALR-041-R includes a built-in LNA. * **Purpose:** To amplify the signal immediately at the source before it travels through a cable, where it might pick up interference. * **Shielding:** The LNA is usually encased in a metal shield to prevent electromagnetic interference (EMI) from local electronics. #### C. Surface Acoustic Wave (SAW) Filter The module incorporates a SAW filter to reject out-of-band signals. This prevents "swamping" or saturation of the GNSS receiver from nearby cellular (LTE/5G) or Wi-Fi transmissions. --- ### 3. Implementation and Schematic Considerations When integrating the ALR-041-R into a PCB design, engineers must consider the **Phantom Power** circuit. ```cpp // Example: Concept of powering the ALR-041-R through the RF line // 1. DC voltage is injected into the RF signal trace via an Inductor (Choke). // 2. A Capacitor is used to block DC from entering the GNSS Receiver chip. [VCC] ---- [Inductor] ----+---- [ALR-041-R Antenna] | [DC Blocking Cap] | [GNSS Receiver IC] ``` ### 4. Application Use-Cases * **Asset Tracking:** High-sensitivity reception for containers or vehicles. * **Telematics:** Reliable positioning for fleet management. * **Time Synchronization:** Providing accurate UTC time for network base stations. ---