The latest cellular network called 5G NR is actually done in 2 steps with FR1 which was covered at cellular antennas and FR2 which introduces a need for 5G mmWave antenna design. FR2 defines a set of new frequencies:
• n257 at 28GHz (26.50-29.50GHz)
• n258 at 26GHz (24.25-27.50GHz)
• n260 at 39GHz (37.00-40.00GHz)
The frequency range differs greatly from the below 6GHz frequencies of earlier cellular bands and introduces several new design challenges.
1. Transmission Path loss
Radiated signal weakens when it moves further away from antenna and the rate at which it happens increases as with frequency. This means that more gain is needed for the antenna unlike earlier cellular systems that benefitted from omnidirectional designs. However, the need for omnidirectional has not disappeared but need to be satisfied as well. Solution for this is an antenna array that can control its main beam direction and thus can point its maximum gain towards base station.
2. Losses in materials
The mechanism of path loss also applies to structures in your device. If the signal needs to go through any material such as plastics or potting materials the signal level is going to drop dramatically. Placement of materials no longer has only tuning effect but attenuation as well.
3. Reflections from materials
If there is more than one material in the transmission path, there is a chance for a reflection to happen. If the signal is reflected, it loses part of its power or, worse, disrupts its radiation pattern and gains in the worst-case, causing blind spots for your device.
4. Transmission-line losses
Due to the higher frequency, you can no longer use long transmission lines on your PCB to your antenna. Material losses are too big. You need to use special PCB materials and/or reduce the length of transmission lines to the absolute minimum.
CoreIoT Services for 5G mmWave antenna design
We offer antenna design services for full product development projects from feasibility studies through different design stages to consultancy at the mass production phase.
Our antenna simulations are critical at reaching accurate performance forecasts in the early stages of development enabling informed decisions before manufacturing prototypes. Simulation enables us to use our extensive know-how in product integration to find new innovative antenna solutions.
We specialize in high performance integrated solutions that are cost-driven. Check our references!