When time and RF engineering experience is of abundance, a designer may opt to use RF integrated circuits (chips or chipsets) to save on RF component costs. Using chips/chipsets, the designer actually develops the hardware and software workings of the product.
While the individual chips/chipsets offer functionality the designer must dictate how those chips will work in concert with the software the designer will develop. This task is not for the faint of heart, as completed designs must also pass rigid regulatory testing for deployment in the various regions of the world. The regulatory approval process alone can become months or years of a cycle of rejection, followed by a reworking of the product and continued by rejection and reworking until the product is approved.
Wireless transceiver (transmitter / receiver) modules offer a faster time-to-market alternative to chips/chipsets that allow designers at all levels of RF experience to integrate a completed wireless system into their products. Many modules are manufactured as a drop-in solution where designers create a compatible pin-out on their processor board and supply serial data to the appropriate pins.
Modules offering the easiest integration allow the designer to send raw UART data into the module and expect that same data out on the receiving end of the wireless link.
Wireless transceiver modules allowing the quickest time-to-market are also FCC and other regulatory agency approved. That means jurisdictions accepting FCC approval allow designers using FCC approved modules to bypass further testing for their wireless products.
In Europe and other countries, pre-approved modules by ETSI and other regulatory bodies allow the designer to deploy products in various regions of the world with minimal additional approvals. The completed RF design and agency approval of many wireless transceiver modules make them a popular choice in the fast-paced world of wireless data communication product design.
Digi Wireless Transceiver Modules
As an example, Digi has a line of wireless transceiver modules that meet many of the performance and ease of use suggestions discussed. Their modules are all drop-in RS-232 / RS-422 / RS-485 solutions that are FCC and other agency approved for use throughout the world. Integrating these wireless data communication solutions is as simple as sending serial data from a microcontroller or comm port, while the Digi module handles all of the complexities of spread spectrum transmission and reception. Of particular note is their ability to communicate at short or long range while consuming low power and maintaining high levels of interference rejection over transparent peer-to-peer, point-to-point, point-to-multipoint and multi-drop networks.
The Digi 9XStream 900 MHz Wireless OEM Module is a frequency-hopping spread spectrum transceiver that uses a simple UART interface to communicate with the host system. It has transmission power output of 140 mW and operates at long ranges (up to ¼ mile in urban environments and up to 20 miles in line-of-sight conditions) due to its excellent receiver sensitivity of –110 dBm. Additionally, the 9XStream uses proprietary filtering technology to provide interference immunity, including 70 dB of cell phone and pager rejection (10 million times attenuation). providing OEMs with a robust, reliable wireless method to transmit serial data.