Sierra Wireless has added five new AirCard 3G data modems to its lineup, including the AirCard 503, AirCard USB and AirCard USB 301/302. The AirCard USB 308 supports 850, 1900 and 2100MHz HSPA+ bands, while the AirCard 309 has 900 and 2100MHz HSPA+ band support. The 503, 309 and AirCard 308 all support high-speed HSPA+ networks, allowing for peak download speeds of 21Mbps. The 503 has a two-in-one design that fits both PC card and ExpressCard slots. The AirCard 503 supports quad-band regular HSPA (850/900/1900/2100MHz) bands. The AirCard 308 and 309 USB modems have a smaller form factor and connect…