14 Replies Latest reply on Apr 8, 2015 6:43 AM by userc_10213

    WI-FI Speed limit Issues on BCM943362WCD4_EVB

      Hello all - I have been using the demo console example program on 2 separate eval boards (DEV A and DEV B). I start Soft AP on DEV A and join the AP on DEV B. I set the data rate on both to 54. Using iperf -s on DEV A and iperf-c on DEVB the max rate I can achieve is 5.8Mbits/sec. I'm not sure but that data rate seems really low. I also tried UDP and the results where much worse.

       

      That said is there way a way to get the data rate between the two devices up to somewhere around 50Mbits/sec. Is there a variable/constant/PCB jumper to jack the rate up? Is there a way to get more concurrent channels open between the two devices.

       

      I plan on using TCP/IP in our upcoming design, and our requirements for throughput is in the 100Mbits/sec area.

       

      Thanks in advance

       

       

      Scott

        • 1. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
          GregG_16

          Hi,

          You need 100mbps? Or do you mean 10mbps?

          The best theoretical max is about 60 percent of your max phy rate. So if your phy is 54 you are looking at 30mbps tcp. I may be off here since there are tricks to play to optimize this.

          Did you try to replace cards with a laptop running iperf and associate to a 2.4G router?

          How is your environment?  Clean from other wifi noise or open air? You can also try laptop to laptop to see what your best case over the air can be.

           

          You can increase your tcp window size in iperf with -w command. For exampie -w 256K in command line. This may help, but not that much.

           

          Send me your exact setup and commands I'll see what I get in the chamber.

          • 2. Re: Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

            Thanks Gangi - Yes I did mean 100Mbits/sec or the same speed as ethernet but over wifi- Is there a way to multiplex and use more channels with WICED.  If I can't acheive 100Mbit/Sec with WICED, does Broadcom offer  a 802.11/ac module available for embedded development activities.

             

            Heres my setup

             

            1. Laptop with 2 BCM943362WCD4 Eval boards connect via USB Com 12 and Com 14

             

            2  Two Sessions of PutTTY running connected to the dev boards with these settings

            2014-05-01 06:59:38 Opening serial device COM14

            2014-05-01 06:59:38 Configuring baud rate 115200

            2014-05-01 06:59:38 Configuring 8 data bits

            2014-05-01 06:59:38 Configuring 1 data bits

            2014-05-01 06:59:38 Configuring no parity

            2014-05-01 06:59:38 Configuring XON/XOFF flow control

             

            3. Each Device has the " test.console-BCM943362WCDR download run"  target on the device. Devices are 1 meter apart.

             

            4. iperf -s on Device A and iperf-c 192.168.0.1 on Device B. Log files are below

             

            5. Log files for  iperf server

             

             

            > start_ap doogie wpa2 password 1

            Setting IPv6 link-local address

            IPv4 network ready IP: 192.168.0.1

            > set_data_rate 54

            > iperf -s

            Spawning a listener.

            ------------------------------------------------------------

            Server listening on TCP port 5001

            TCP window size: 8.00 KByte (default)

            ------------------------------------------------------------

            Spawning a server.

            [ ID] Interval       Transfer     Bandwidth

            [  0]  0.0-10.0 sec  6.98 MBytes  5.85 Mbits/sec

            Spawning a server.

            [  0]  0.0-10.0 sec  7.49 MBytes  6.28 Mbits/sec

             

            6. Log file for iperf client

             

            > join doogie wpa2 password

            Joining : doogie

            Successfully joined : doogie

            Obtaining IPv4 address via DHCP

            Setting IPv6 link-local address

            IPv4 network ready IP: 192.168.0.2

            > set_data_rate 54

            > iperf -c 192.168.0.1

            ------------------------------------------------------------

            Client connecting to 192.168.0.1, TCP port 5001

            TCP window size: 8.00 KByte (default)

            ------------------------------------------------------------

            [ ID] Interval       Transfer     Bandwidth

            [  0]  0.0-10.0 sec  6.98 MBytes  5.86 Mbits/sec

            > iperf -c 192.168.0.1 -w 256k

            ------------------------------------------------------------

            Client connecting to 192.168.0.1, TCP port 5001

            TCP window size: 8.00 KByte (WARNING: requested  256 KByte)

            ------------------------------------------------------------

            [  0]  0.0-10.0 sec  7.49 MBytes  6.28 Mbits/sec

            • 3. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
              SeyhanA_31

              Hi Scott,

               

              WICED does not target bandwidth you are asking at this time. You may consider Broadcom WiFi radios with different CPUs.

               

              - Seyhan

              • 4. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                The 43362 is a 1x1 802.11n device with a theoretical maximum rate of 72 mbps (assuming short guard interval) or 65mbps otherwise. As Greg already mentioned environment and protocol overheads reduce that significantly.

                Our testing has shown that, for ThreadX-NetX_Duo, the following throughputs are achievable from a BCM943362WCD4 device to a laptop via a router:

                  

                UDP Tx28.6 mbps
                UDP Rx

                39.6 mbps

                  

                TCP Tx 27.7 mbps
                TCP Rx13.3 mbps
                1 of 1 people found this helpful
                • 5. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
                  MiTo_1583836

                  Hi nikvh,

                   

                  Could you clarify the test setup to achieve the throughput listed in your post?

                   

                  Is the measure performed at the application processor level using the WICED API?

                   

                  When you do the transmission of packets, are you generating traffic from a WICED application running on the application processor? (I believe yes, just want to make sure).

                   

                  Thanks

                  • 6. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                    Hi

                     

                    Did you got the result as mentioned above ?

                    with stm32f429 mcu + sn800 i'm getting 1Mbits/s only

                    Any suggestion?

                    • 7. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
                      JoYi_1844281

                      Which interface SDIO/SPI  to connect WIFI ?

                      • 8. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                        I'm using SDIO interface

                        • 9. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
                          JoYi_1844281

                          How fast your SDIO clock ?

                          How to connect your WIFI via SDIO of MCU ? jump wiring or have custom PCB ?

                          SDIO interface is running in one-bit or 4-bit mode ? HighSpeed enable or not ?

                           

                          If you connect your MCU SDIO to WiFi via jump wiring ! The throughput will NOT Good !

                           

                          And you should running the throughput test in chamber !

                          • 10. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                            Actally I replcated the same behaviour on SN8000x Evaluation board from Murata. Which has support on Wiced.

                             

                            SDIO 25Mhz, In EVB & my custom board its connected on PCB , I suppose 4 bit mode & high speed is enabled may be that's why I'm getting 25Mhz

                             

                            I should be able to get a throughtput of at least 4-8Mb/s right?

                            • 11. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
                              JoYi_1844281

                              Suppose 4Mb/s is reasonable number!

                              • 12. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                                But as per now I only get 1Mb/s (UDP packet creation+sending of 8ms).

                                 

                                How can I improve this?

                                • 13. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB
                                  JoYi_1844281

                                  Did you run throughput test via iperf in  test.console ?

                                  We are talking throughput  result via iperf!

                                   

                                  If you did not done it yet, You should do it now!

                                   

                                  If you got the same low throughput! I guess your system is not well design in H/W!

                                  You should review your H/W first!

                                  • 14. Re: WI-FI Speed limit Issues on BCM943362WCD4_EVB

                                    Ok, i sorted it out .

                                     

                                    I was using debug alongwith the build string which caused high duration of packet creation + sending, (not clear why is this)

                                     

                                    When I removed it I got creation+sending under 200-400microseconds, which is a good throughput