Скорости 802.11n на BCM4313

Я создал точку доступа точки доступа, используя следующую конфигурацию hostapd:

#####Basic Settings########################
#sets the wifi interface to use, is wlan0 in most cases
interface=wlan0
#driver to use, nl80211 works in most cases
driver=nl80211
#Access Point name
ssid=HEXspot

#####Channel and Mode Settings#############
# Operation mode (a = IEEE 802.11a, b = IEEE 802.11b, g = IEEE 802.11g,
# ad = IEEE 802.11ad (60 GHz); a/g options are used with IEEE 802.11n, too, to
# specify band)
# Default: IEEE 802.11b
hw_mode=g
# WiFi Channel:
channel=11

##### IEEE 802.11n related configuration ##
#WMM needs to be enabled for full HT functionality
wmm_enabled=1
# ieee80211n: Whether IEEE 802.11n (HT) is enabled
# 0 = disabled (default)
# 1 = enabled
# Note: You will also need to enable WMM for full HT functionality.
ieee80211n=1
# ht_capab: HT capabilities (list of flags)
# LDPC coding capability: [LDPC] = supported
# Supported channel width set: [HT40-] = both 20 MHz and 40 MHz with secondary
#   channel below the primary channel; [HT40+] = both 20 MHz and 40 MHz
#   with secondary channel below the primary channel
#   (20 MHz only if neither is set)
#   Note: There are limits on which channels can be used with HT40- and
#   HT40+. Following table shows the channels that may be available for
#   HT40- and HT40+ use per IEEE 802.11n Annex J:
#   freq        HT40-       HT40+
#   2.4 GHz     5-13        1-7 (1-9 in Europe/Japan)
#   5 GHz       40,48,56,64 36,44,52,60
#   (depending on the location, not all of these channels may be available
#   for use)
#   Please note that 40 MHz channels may switch their primary and secondary
#   channels if needed or creation of 40 MHz channel maybe rejected based
#   on overlapping BSSes. These changes are done automatically when hostapd
#   is setting up the 40 MHz channel.
# Spatial Multiplexing (SM) Power Save: [SMPS-STATIC] or [SMPS-DYNAMIC]
#   (SMPS disabled if neither is set)
# HT-greenfield: [GF] (disabled if not set)
# Short GI for 20 MHz: [SHORT-GI-20] (disabled if not set)
# Short GI for 40 MHz: [SHORT-GI-40] (disabled if not set)
# Tx STBC: [TX-STBC] (disabled if not set)
# Rx STBC: [RX-STBC1] (one spatial stream), [RX-STBC12] (one or two spatial
#   streams), or [RX-STBC123] (one, two, or three spatial streams); Rx STBC
#   disabled if none of these set
# HT-delayed Block Ack: [DELAYED-BA] (disabled if not set)
# Maximum A-MSDU length: [MAX-AMSDU-7935] for 7935 octets (3839 octets if not
#   set)
# DSSS/CCK Mode in 40 MHz: [DSSS_CCK-40] = allowed (not allowed if not set)
# PSMP support: [PSMP] (disabled if not set)
# L-SIG TXOP protection support: [LSIG-TXOP-PROT] (disabled if not set)
ht_capab=[HT40][GF][SHORT-GI-40][SHORT-GI-20]
# Require stations to support HT PHY (reject association if they do not)
require_ht=1

#####Security and Authentication###########
#macaddr_acl sets options for mac address filtering. 0 means "accept unless in deny list"
macaddr_acl=0
#Sets authentication algorithm
#1 - only open system authentication
#2 - both open system authentication and shared key authentication
auth_algs=1
#setting ignore_broadcast_ssid to 1 will disable the broadcasting of ssid
ignore_broadcast_ssid=0

#####Sets WPA and WPA2 authentication######
#wpa option sets which wpa implementation to use
#1 - wpa only
#2 - wpa2 only
#3 - both
wpa=2
#sets WPA Password required by the clients to authenticate themselves on the network
wpa_passphrase=anything
#sets wpa key management
wpa_key_mgmt=WPA-PSK
#sets encryption used by WPA2
rsn_pairwise=CCMP

Моя система Ubuntu 12.04.4 с linux-generic -lts-saucy kernel (ядро Saucy's 3.11, включенное в Ubuntu 12.04LTS). Я использовал драйвер brcmsmac wireless, который получил поддержку режима AP от ядра 3.10 и далее. Мне удалось получить скорость передачи 72 Мбит / с 802.11n на частоте 2,4 ГГц с шириной канала 20 МГц. Но, как и в вашем случае, фактическая скорость передачи меньше 1 Мбит / с, даже для FTP-передач. Поскольку BCM4313 не может работать на частоте 5 ГГц, мы все равно не можем получить канальные скорости n-mode. Лучше всего получить ширину канала 40 МГц (режим HT40) в диапазоне 2,4 ГГц. Проблема в том, что brcmsmac не поддерживает режим 40 МГц в полосе 2,4 ГГц, по крайней мере для BCM4313. Также нет поддержки режима DSSS / CCK. Я надеюсь, что драйвер улучшится в новых ядрах. Когда Ubuntu 14.04 Trusty Tahr будет выпущен, я попробую это снова с его ядром 3.13.