2 * Copyright (c) 2003, 2004 David Young. All rights reserved.
4 * Redistribution and use in source and binary forms, with or
5 * without modification, are permitted provided that the following
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above
10 * copyright notice, this list of conditions and the following
11 * disclaimer in the documentation and/or other materials provided
12 * with the distribution.
13 * 3. The name of David Young may not be used to endorse or promote
14 * products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
19 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
20 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL David
21 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
30 * $NetBSD: ieee80211_rssadapt.h,v 1.4 2005/02/26 22:45:09 perry Exp $
31 * $FreeBSD: src/sys/dev/ral/if_ralrate.h,v 1.1 2005/04/18 18:47:36 damien Exp $
32 * $DragonFly: src/sys/dev/netif/ral/Attic/if_ralrate.h,v 1.1 2006/05/20 09:13:09 sephe Exp $
35 /* Data-rate adaptation loosely based on "Link Adaptation Strategy
36 * for IEEE 802.11 WLAN via Received Signal Strength Measurement"
37 * by Javier del Prado Pavon and Sunghyun Choi.
40 /* Buckets for frames 0-128 bytes long, 129-1024, 1025-maximum. */
41 #define RAL_RSSADAPT_BKTS 3
42 #define RAL_RSSADAPT_BKT0 128
43 #define RAL_RSSADAPT_BKTPOWER 3 /* 2**_BKTPOWER */
45 #define ral_rssadapt_thresh_new \
46 (ral_rssadapt_thresh_denom - ral_rssadapt_thresh_old)
47 #define ral_rssadapt_decay_new \
48 (ral_rssadapt_decay_denom - ral_rssadapt_decay_old)
49 #define ral_rssadapt_avgrssi_new \
50 (ral_rssadapt_avgrssi_denom - ral_rssadapt_avgrssi_old)
52 struct ral_rssadapt_expavgctl {
53 /* RSS threshold decay. */
56 /* RSS threshold update. */
57 u_int rc_thresh_denom;
59 /* RSS average update. */
60 u_int rc_avgrssi_denom;
65 /* exponential average RSSI << 8 */
66 u_int16_t ra_avg_rssi;
67 /* Tx failures in this update interval */
69 /* Tx successes in this update interval */
71 /* exponential average packets/second */
73 /* RSSI threshold for each Tx rate */
74 u_int16_t ra_rate_thresh[RAL_RSSADAPT_BKTS]
75 [IEEE80211_RATE_SIZE];
76 struct timeval ra_last_raise;
77 struct timeval ra_raise_interval;
80 /* Properties of a Tx packet, for link adaptation. */
82 u_int id_len; /* Tx packet length */
83 u_int id_rateidx; /* index into ni->ni_rates */
84 struct ieee80211_node *id_node; /* destination STA MAC */
85 u_int8_t id_rssi; /* destination STA avg RSS @
90 void ral_rssadapt_updatestats(struct ral_rssadapt *);
91 void ral_rssadapt_input(struct ieee80211com *, struct ieee80211_node *,
92 struct ral_rssadapt *, int);
93 void ral_rssadapt_lower_rate(struct ieee80211com *,
94 struct ieee80211_node *, struct ral_rssadapt *,
95 struct ral_rssdesc *);
96 void ral_rssadapt_raise_rate(struct ieee80211com *,
97 struct ral_rssadapt *, struct ral_rssdesc *);
98 int ral_rssadapt_choose(struct ral_rssadapt *,
99 struct ieee80211_rateset *, struct ieee80211_frame *, u_int,