Access switching-in portTechnical field
The invention belongs to wireless communication field, specially refer to access switching-in port.
Background technology
Wired local area network is by hub (switch, the meaning is the jack conversion) and the network interface card composition, cable network has been subjected to more restriction in communication, the distance of two websites is when using copper cable, be limited in 500 meters, even adopt monomode fiber also can only reach 3 kilometers, and in the WLAN (wireless local area network), the distance between two websites can reach 50 kilometers at present, owing to there is not the restriction of cable, the user can indiscriminately ad. as one wishes increase work station or reconfigure work station, communication range is subjected to the environmental condition restriction little, has widened the transmission range of network, and wireless network networking flexibility height, increase WAP (wireless access point), just can increase number of users and coverage, and allow in a big way, to roam, simultaneously, for wired network, the wireless network cost is low, antijamming capability is strong; Throughput is big, can realize the message transmission rate of 11Mbps; The reliability height can be realized message transmission in narrower frequency bandwidth; Its code division multiple access ability is strong, " access switching-in port " that the inventor researched and developed, be called for short Access Point Clinet, AP clinet, client and wireless network card that this pattern is equivalent to Access Point pattern are in equivalent effect, different is that this Clinet connects finite element network or single device only, communicate by letter with other wireless network card or finite element network by ap, the operation principle of AP clinet is to adopt the mode of operation identical with wireless network card, before the transmission data, whether intercept channel idle, the idle request that then sends rts requirement transfer of data to AP is arranged, AP agrees that the back sends cts, stops other user capture, and the request user begins transfer of data.In this way, any one work station in the WLAN (wireless local area network) can be successfully with the center local area network (LAN) in any one work station communicate, do not need driver just can connect the equipment of any computer or support Etbernet port, computer or equipment are coupled together by AP and network, realize network service, as a client, AP clinet must be arranged to identical ESSID with main AP, identical wireless channel.And in " PreferredBSS ID " MAC Address number of the main AP of input, many AP clinet just can communicate by letter with an AP as network interface card like this, to set up network, AP clinet radio network technique adopts 802.11b, because what use is the open frequency range (between the 2.4G-2.48G) of State Radio Regulatory Commission's permission, thereby be widely used in civilian every field, and as: industry, retail business, warehouse, harbour, medical treatment or the like.
Summary of the invention
The technical issues that need to address of the present invention, be that the microcomputer in the wireless network is communicated by wireless mode, real-time information service all is provided anywhere, break away from the cable network cable constraint and weak point such as restricted strengthens mobility, not only support the communication between the mobile host, also allow wireless device to have access to spider lines, make communication range reduced by the environmental condition restriction, widen the transmission range of network.To achieve these goals, researched and developed AP clinet radio network technique (802.11b), they are realized by the following technical solutions, a kind of access switching-in port, comprise Ethernet preach interface circuit, change-over circuit and radio frequency module circuit, it is characterized in that, described ethernet interface circuit and change-over circuit, be the circuit signal that the physical layer signal transition that ethernet line transmits is become the IEEE802.3 MII of international standard, in coupled bridge-type chip circuit, the Datagram of IEEE802.3 converted to the standard of IEEE802.116; This bridge-type chip circuit connects baseband circuit, in base band, is the signal (I/O) of fundamental frequency with the numerical digit modulating signal, and what link to each other with baseband circuit is radio frequency module circuit, and it changes fundamental frequency signal into high-frequency signal, and will send after the signal amplification; Signal for being received by the AP access point along the reversible path of input signal, is connected with radio-frequency module, baseband circuit, bridge-type chip-count word signal processing circuit and ethernet interface circuit respectively, externally connects by switch.In bridging chip, comprise two parts of internal memory and flash memory; The working method of described access switching-in port, it is the wireless stream of data that the TCP/IP data flow is converted to WLAN, this practice can make full use of existing resource, can under the precondition that does not change any software and hardware structure, realize wireless network, fully guaranteed the original investment of enterprise, be unlikely to carry out a large amount of equipment and eliminate.The working method of AP clinet can not need driver fully in the data flow conversion that protocol layer carries out TCP/IP (referring to a kind of reference format) and WLAN (referring to wireless), as long as system can support the TCP/IP data flow, just the corresponding wireless stream of data that is converted into of energy realizes comprehensive covering of wireless network.Utilize 128 WEP cipher modes to encrypt, can guarantee the fail safe of sensitive data, the invention has the beneficial effects as follows, under the secure scheme of multi-enciphering, can realize that wireless network is more safe and reliable than cable network, make and have only the wireless terminal of mandate just can land and accesses network, illegal terminal can't land, and has guaranteed the validated user safety of data.
Description of drawings
The circuit design block diagram that Fig. 1 accesses terminal for the present invention
The job step schematic diagram that Fig. 2 accesses terminal for the present invention.
Embodiment
With reference to Fig. 1,2 indication circuits design block diagram, whereinethernet interface circuit 1, adoptable chip is RTL8201, network transmission physical layer signal (MLT-3) is transformed into the IEEE802.3 standard MII signal of international standard thus, coupled isbridging chip 2, this chip is responsible for the rule process that Digital Signal Processing (CPU) is finished the agreement of 802.11b, available chip is AT76C510,2.1 be Installed System Memory SRAM, 2.2 be the flash memory of system, the configuration information of storage system and program code, behind the system cut-off, data can not lost, what link to each other withchip 2 is base band 3, it becomes low frequency signal with the high-frequency microwave data transaction, convert digital signal again to, the chip that it can be selected for use is HFA3861B, the part of Xiang Lianing is a radio-frequency module 4 at last, after it is transformed into high-frequency signal with fundamental frequency signal, again signal is amplified and launch, or will give base band 3 processing again after the signal amplification that receive, the chip that it is selected for use can be ISL3683/ISL3782/HFA3983, A represents from the outside signal that sends of PC through each step of 1-4 among Fig. 2, B represents the signal by the AP reception, via 4-1 each several part circuit, change physical layer signal (MLT-3) at last into and finish digital-to-analogue conversion respectively.