
It is important therefore to evaluate the range and performance of wireless transmission to create models for estimating the path loss for short range modules in indoor and outdoor environments to give designers an initial estimate on a wireless communications system’s performance. The performance parameters include range, path loss, receiver sensitivity, bit error rate (BER) and packet error rate (PER), which are critical in any communications system.
To do this, consider three modules with varied specifications related to power and type of antenna – Microchip’s MRF24J40MA, MRF24J40MB and MRF24J40MC. The MRF24J40MA is a certified 2.4 GHz IEEE 802.15.4 radio transceiver module with integrated PCB antenna and is suitable for wireless sensor networks, home automation, building automation and consumer applications. The MRF24J40MB is similar but better suited to longer range applications such as automatic meter reading. The MRF24J40MC has an external antenna (shown in Figure 1) and also suits longer range applications. All three connect to microcontrollers through a four-wired SPI interface and have various regulatory and modularly certified on board.
Figure 1: MRF24J40MC modules with daughter board and external antenna.