Mini PCI Cards for Bluetooth and Wifi Connections
Early adapters of WiFi often had a difficult time manually configuring their notebook computers for wireless networking. Making changes to their notebook often resulted in an inoperable network connection. Dell, Hewlett- Packard, IBM, Sony, and Toshiba are among the growing number of computer companies that offer integrated WiFi capabilities in their notebooks, putting an end to manual configurations. The WiFi antennas are embedded directly into the lid of the notebook for optimal signal strength, eliminating the need for a PC Card.
The WiFi radio is contained on a very small card called the Mini PCI, which is functionally identical to standard desktop computer PCI Cards but can be slotted on the computer’s main board (see picture above). Many laptop manufacturers have adopted the Mini PCI form factor to add integral support for wireless networking and modems, enabling PC Card slots to remain free for other options.
The Mini PCI Card offers several advantages over current proprietary and vendor-specific integrated communications devices, which are not designed to be replaced when they fail or upgraded when technology changes. In contrast, depending on the particular system design, a service technician can replace a standard Mini PCI Card if it fails or needs an upgrade rather than replacing the entire system board, which entails a higher cost to the customer.
Mini PCI Cards can support other wireless technologies, including Bluetooth and GPRS, as well as wire technologies such as G.lite, a variation of Asymmetrical Digital Subscriber Line (ADSL), and IEEE 1394, also known as FireWire. Some Mini PCI Cards also support multiple communications technologies. For example, one Mini PCI Card could provide both Bluetooth and WiFi connections. WLAN chip-set provider Intersil and Bluetooth radio maker Silicon Wave have devised a reference design called Blue802, which allows for the near simultaneous operation of the Bluetooth and WiFi wireless protocols.
A notebook equipped with a Blue802 Mini PCI Card could run a video stream to a WLAN AP while sending data to a printer via Bluetooth. This also enables PC-based Bluetooth applications such as mouse, keyboard, printing, file transfer, and portable device synchronization to run at the same time the user’s PC is connected to a network over WiFi.
Bluetooth and WiFi operate in the same 2.4 GHz radio band, but because Bluetooth employs frequency hopping, it jumps all over the band, slowing down and even terminating WiFi connections. The Blue802 technology overcomes this obstacle by using a time-slicing technique in which the two protocols are not actually running simultaneously, but switch back and forth so fast that the connection seems simultaneous.