How to use multiband embedded antennas in IoT designs
Antenna design can make or break a wireless product. The challenge is even greater for an increasingly diverse array of wireless Internet of Things (IoT) designs where regulations limit the transmit power in the allocated frequency bands, even as the engineer strives to maximise throughput and range. Conventional design guidelines advise strip antennas with a length of half the wavelength of the signal it is intended to receive. For a dipole antenna, this translates to 6.25cm for the 2.4GHz frequency band. But for wireless IoT products, this design advice presents two
major challenges. First, space is typically at a premium, so accommodating a relatively lengthy antenna is difficult. Second, IoT products typically access multiple radio frequencies to connect to Bluetooth low energy (Bluetooth LE), Wi-Fi, GPS, and/or cellular. This means having to accommodate multiple antennas, each requiring their own impedance matching circuit, which adds to the cost, complexity, and bulk of the design. Embedded antennas offer a solution to the space and cost constraints of multiband IoT product design. These monolithic
Contributed By: Steven Keeping, Contributing Author, Digikey
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