What are the maximum transmission speeds achievable with CDPD?

The maximum transmission speeds achievable with Cellular Digital Packet Data (CDPD) technology can reach up to 19.2 kbits/sec. CDPD was developed to allow packet-switched data transmission over existing wireless networks, originally using the AMPS (Advanced Mobile Phone System) infrastructure. The specified speed of 19.2 kbits/sec reflects the capability of CDPD to deliver data efficiently while adapting to the existing cellular technology of the time.

This speed represents a significant advancement for mobile data transmission at that era, allowing for more robust applications such as mobile internet and email services, enhancing user experience compared to earlier technologies. The choice of 19.2 kbits/sec is often highlighted in discussions about CDPD due to its practical use in early mobile data communications, setting a standard for packet-switched data services in a cellular environment.

In contrast, other given options suggest higher speeds that are not representative of CDPD capabilities, as the technology was limited to the 19.2 kbits/sec mark under optimal conditions. Thus, the answer reflects the accurate operational limits of the CDPD technology within its design and the telecommunications landscape during its implementation.