4-Antenna feeder
If your design includes a radio transmitter, receiver, or transceiver (transmitter receiver combination), then it must have an antenna. For optimal performance, the feed lines between the RF pins on the RF chip should match the impedance of the feed lines they are connected to. Conversely, the feeder must match the impedance of the antenna. In order to maximize power transmission between the antenna and the RF chip, this impedance matching is necessary. Any mismatch will result in a decrease in actual transmission power, thereby narrowing the working range.
The feed line is just a PCB tracking line with matching antenna impedance (usually 50 Ω). If the output impedance of the transmitter does not match the impedance of the feeder, a matching network composed of inductors and capacitors is usually used. In order to achieve impedance control, the feeder is a PCB tracking line with a calculated width extending to the ground plane. The width of the tracking line depends on the thickness of the copper wire, the thickness of the PCB substrate, and the dielectric constant.
There are many online tools available to calculate the exact width required for a given copper thickness and substrate material, preferably confirmed in actual PCBs. My favorite is a free software called AppCad, which can be downloaded from Broadcom. If the antenna is a PCB antenna, it should be located on one side of the PCB without any ground plane.
Any other signs should be removed, and any large components should be kept away. Screen printing around the antenna is usually good, but copper screen printing (such as PCB number or company name) may cause antenna misalignment.
If your design includes a radio transmitter, receiver, or transceiver (transmitter receiver combination), then it must have an antenna. For optimal performance, the feed lines between the RF pins on the RF chip should match the impedance of the feed lines they are connected to. Conversely, the feeder must match the impedance of the antenna. In order to maximize power transmission between the antenna and the RF chip, this impedance matching is necessary. Any mismatch will result in a decrease in actual transmission power, thereby narrowing the working range.
The feed line is just a PCB tracking line with matching antenna impedance (usually 50 Ω). If the output impedance of the transmitter does not match the impedance of the feeder, a matching network composed of inductors and capacitors is usually used. In order to achieve impedance control, the feeder is a PCB tracking line with a calculated width extending to the ground plane. The width of the tracking line depends on the thickness of the copper wire, the thickness of the PCB substrate, and the dielectric constant.
There are many online tools available to calculate the exact width required for a given copper thickness and substrate material, preferably confirmed in actual PCBs. My favorite is a free software called AppCad, which can be downloaded from Broadcom. If the antenna is a PCB antenna, it should be located on one side of the PCB without any ground plane.
Any other signs should be removed, and any large components should be kept away. Screen printing around the antenna is usually good, but copper screen printing (such as PCB number or company name) may cause antenna misalignment.
