User Manual Part 2

CY8CKIT-042-BLE Bluetooth® Low Energy (BLE) Pioneer Kit Guide, Doc. # 001-93731 Rev. *A 109
Hardware
5.2.4 Antenna Matching Network
An Antenna Matching Network is required between the BLE device and the antenna to achieve opti-
mum performance (Figure 5-23). The matching network has four main tasks:
■ Transform the balanced output of the radio to an unbalanced connection to the antenna (balun).
■ Transform the output impedance of the radio to a 50-ohm antenna.
■ Suppress harmonics to a level below the regulations level in TX mode.
■ Suppress the local oscillator (LO) leakage in RX mode.
Figure 5-23. Schematics and Board Highlight of Antenna Matching Network and Antenna