Hostapd AC signal low

Hello,

I'm having trouble with a extremly low wifi signal on a newly built router based on PC Engines APU.2D4 system with a
MikroTik R11e-5HacD miniPCI-e karta 802.11ac, 2 x MMCX, Atheros (5 GHz) card & a 9dBi omnidirectional antenna.

This is what I'm getting being just 4.5 meters away from the router.
MUGEN is my ssid:

Compare it to my upstairs neighbor TypeR ssid. He is running something called "Compal modem" that he received from his provider. This device is located one floor above me, 10 meters away and trough a concrete ceiling.

My hostapd config:

interface=wlp4s0
driver=nl80211
logger_syslog=-1
logger_syslog_level=2
logger_stdout=-1
logger_stdout_level=2
debug=4
channel=44
ieee80211d=1
country_code=SK
hw_mode=a
macaddr_acl=0
auth_algs=3
eapol_key_index_workaround=0
eap_server=0
wpa=2
ssid=MUGEN
wpa_passphrase=whatever
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP
eapol_version=1
wme_enabled=1
wmm_enabled=1
wmm_ac_bk_cwmin=4
wmm_ac_bk_cwmax=10
wmm_ac_bk_aifs=7
wmm_ac_bk_txop_limit=0
wmm_ac_bk_acm=0
wmm_ac_bk_cwmin=4
wmm_ac_bk_cwmax=10
wmm_ac_bk_aifs=7
wmm_ac_bk_txop_limit=0
wmm_ac_bk_acm=0
wmm_ac_be_aifs=3
wmm_ac_be_cwmin=4
wmm_ac_be_cwmax=10
wmm_ac_be_txop_limit=0
wmm_ac_be_acm=0
wmm_ac_vi_aifs=2
wmm_ac_vi_cwmin=3
wmm_ac_vi_cwmax=4
wmm_ac_vi_txop_limit=94
wmm_ac_vi_acm=0
wmm_ac_vo_aifs=2
wmm_ac_vo_cwmin=2
wmm_ac_vo_cwmax=3
wmm_ac_vo_txop_limit=47
wmm_ac_vo_acm=0
ieee80211n=1
ieee80211ac=1
ht_capab=[HT40+][SHORT-GI-40][DSSS_CCK-40][MAX-AMSDU-3839]
vht_capab=[MAX-MPDU-11454][MAX-A-MPDU-LEN-EXP0][SHORT-GI-80]
vht_oper_chwidth=1
vht_oper_centr_freq_seg0_idx=42
#vht_oper_centr_freq_seg1_idx=159

iw outputs:

root@xxx:~# iw wlp4s0 info
Interface wlp4s0
        ifindex 6
        wdev 0x1
        addr cc:2d:e0:91:19:b3
        ssid MUGEN
        type AP
        wiphy 0
        channel 44 (5220 MHz), width: 80 MHz, center1: 5210 MHz
        txpower 20.00 dBm
        multicast TXQ:
                qsz-byt qsz-pkt flows   drops   marks   overlmt hashcol tx-bytes        tx-packets
                0       0       3455465 0       0       0       0       962880010               3455465
root@xxx:~# iw list
Wiphy phy0
        max # scan SSIDs: 16
        max scan IEs length: 199 bytes
        max # sched scan SSIDs: 0
        max # match sets: 0
        max # scan plans: 1
        max scan plan interval: -1
        max scan plan iterations: 0
        Retry short limit: 7
        Retry long limit: 4
        Coverage class: 0 (up to 0m)
        Device supports RSN-IBSS.
        Device supports AP-side u-APSD.
        Supported Ciphers:
                * WEP40 (00-0f-ac:1)
                * WEP104 (00-0f-ac:5)
                * TKIP (00-0f-ac:2)
                * CCMP-128 (00-0f-ac:4)
                * CMAC (00-0f-ac:6)
                * CMAC-256 (00-0f-ac:13)
                * GMAC-128 (00-0f-ac:11)
                * GMAC-256 (00-0f-ac:12)
        Available Antennas: TX 0x3 RX 0x3
        Configured Antennas: TX 0x3 RX 0x3
        Supported interface modes:
                 * managed
                 * AP
                 * monitor
                 * mesh point
        Band 2:
                Capabilities: 0x19ef
                        RX LDPC
                        HT20/HT40
                        SM Power Save disabled
                        RX HT20 SGI
                        RX HT40 SGI
                        TX STBC
                        RX STBC 1-stream
                        Max AMSDU length: 7935 bytes
                        DSSS/CCK HT40
                Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
                Minimum RX AMPDU time spacing: 8 usec (0x06)
                HT TX/RX MCS rate indexes supported: 0-15
                VHT Capabilities (0x338001b2):
                        Max MPDU length: 11454
                        Supported Channel Width: neither 160 nor 80+80
                        RX LDPC
                        short GI (80 MHz)
                        TX STBC
                        RX antenna pattern consistency
                        TX antenna pattern consistency
                VHT RX MCS set:
                        1 streams: MCS 0-9
                        2 streams: MCS 0-9
                        3 streams: not supported
                        4 streams: not supported
                        5 streams: not supported
                        6 streams: not supported
                        7 streams: not supported
                        8 streams: not supported
                VHT RX highest supported: 0 Mbps
                VHT TX MCS set:
                        1 streams: MCS 0-9
                        2 streams: MCS 0-9
                        3 streams: not supported
                        4 streams: not supported
                        5 streams: not supported
                        6 streams: not supported
                        7 streams: not supported
                        8 streams: not supported
                VHT TX highest supported: 0 Mbps
                Bitrates (non-HT):
                        * 6.0 Mbps
                        * 9.0 Mbps
                        * 12.0 Mbps
                        * 18.0 Mbps
                        * 24.0 Mbps
                        * 36.0 Mbps
                        * 48.0 Mbps
                        * 54.0 Mbps
                Frequencies:
                        * 5180 MHz [36] (20.0 dBm)
                        * 5200 MHz [40] (20.0 dBm)
                        * 5220 MHz [44] (20.0 dBm)
                        * 5240 MHz [48] (20.0 dBm)
                        * 5260 MHz [52] (20.0 dBm) (no IR, radar detection)
                        * 5280 MHz [56] (20.0 dBm) (no IR, radar detection)
                        * 5300 MHz [60] (20.0 dBm) (no IR, radar detection)
                        * 5320 MHz [64] (20.0 dBm) (no IR, radar detection)
                        * 5500 MHz [100] (23.0 dBm) (no IR, radar detection)
                        * 5520 MHz [104] (23.0 dBm) (no IR, radar detection)
                        * 5540 MHz [108] (23.0 dBm) (no IR, radar detection)
                        * 5560 MHz [112] (23.0 dBm) (no IR, radar detection)
                        * 5580 MHz [116] (23.0 dBm) (no IR, radar detection)
                        * 5600 MHz [120] (23.0 dBm) (no IR, radar detection)
                        * 5620 MHz [124] (23.0 dBm) (no IR, radar detection)
                        * 5640 MHz [128] (23.0 dBm) (no IR, radar detection)
                        * 5660 MHz [132] (23.0 dBm) (no IR, radar detection)
                        * 5680 MHz [136] (23.0 dBm) (no IR, radar detection)
                        * 5700 MHz [140] (23.0 dBm) (no IR, radar detection)
                        * 5720 MHz [144] (disabled)
                        * 5745 MHz [149] (disabled)
                        * 5765 MHz [153] (disabled)
                        * 5785 MHz [157] (disabled)
                        * 5805 MHz [161] (disabled)
                        * 5825 MHz [165] (disabled)
                        * 5845 MHz [169] (disabled)
                        * 5865 MHz [173] (disabled)
        Supported commands:
                 * new_interface
                 * set_interface
                 * new_key
                 * start_ap
                 * new_station
                 * new_mpath
                 * set_mesh_config
                 * set_bss
                 * authenticate
                 * associate
                 * deauthenticate
                 * disassociate
                 * join_ibss
                 * join_mesh
                 * remain_on_channel
                 * set_tx_bitrate_mask
                 * frame
                 * frame_wait_cancel
                 * set_wiphy_netns
                 * set_channel
                 * set_wds_peer
                 * probe_client
                 * set_noack_map
                 * register_beacons
                 * start_p2p_device
                 * set_mcast_rate
                 * connect
                 * disconnect
                 * channel_switch
                 * set_qos_map
                 * set_multicast_to_unicast
        Supported TX frame types:
                 * IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * mesh point: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
                 * P2P-device: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
        Supported RX frame types:
                 * IBSS: 0x40 0xb0 0xc0 0xd0
                 * managed: 0x40 0xd0
                 * AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
                 * AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
                 * mesh point: 0xb0 0xc0 0xd0
                 * P2P-client: 0x40 0xd0
                 * P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
                 * P2P-device: 0x40 0xd0
        software interface modes (can always be added):
                 * monitor
        valid interface combinations:
                 * #{ AP, mesh point } <= 8, #{ managed } <= 1,
                   total <= 8, #channels <= 1, STA/AP BI must match
        HT Capability overrides:
                 * MCS: ff ff ff ff ff ff ff ff ff ff
                 * maximum A-MSDU length
                 * supported channel width
                 * short GI for 40 MHz
                 * max A-MPDU length exponent
                 * min MPDU start spacing
        Device supports TX status socket option.
        Device supports HT-IBSS.
        Device supports SAE with AUTHENTICATE command
        Device supports scan flush.
        Device supports AP scan.
        Device supports per-vif TX power setting
        Driver supports full state transitions for AP/GO clients
        Driver supports a userspace MPM
        Driver/device bandwidth changes during BSS lifetime (AP/GO mode)
        Device supports static SMPS
        Device supports configuring vdev MAC-addr on create.
        Supported extended features:
                * [ VHT_IBSS ]: VHT-IBSS
                * [ RRM ]: RRM
                * [ SET_SCAN_DWELL ]: scan dwell setting
                * [ FILS_STA ]: STA FILS (Fast Initial Link Setup)
                * [ CQM_RSSI_LIST ]: multiple CQM_RSSI_THOLD records
                * [ CONTROL_PORT_OVER_NL80211 ]: control port over nl80211
                * [ TXQS ]: FQ-CoDel-enabled intermediate TXQs

Please help, I have no idea how to solve this.

I have not used this card but with similar I found using two antennas was required. With just a single antenna, the driver detects the missing one and dramatically reduces power.
You say you only have one antenna......

Yes that is correct. I will get a second one to test.

Is there a 5Ghz AC antenna that you'd recommend ?

Thank you.

Where did you get the one you have? They usually come with a connector and pigtail. It is probably best to have a matching pair.

Some local supplier. I will order second one will see if it helps.
I have also found this one, if the first doesnt work:
https://www.wifi-shop24.com/CONEXUM-24/5GHz-2x2MIMO-Omni-Antenna-Band-Filter-ac/ax

That does not look suitable for the PC Engines case at all.
You need something like this (or maybe not - see edit):


EDIT This card has mmcx connectors (fairly rare) so you need special pigtails:

Hello, short update, I have purchased second antenna same as the first. It did not help one bit.

I'm thinking that maybe there is a difference between 5Ghz and 5Ghz rated for AC.

So now I will try to find a pair that is AC rated.