2 /* $FreeBSD: head/sys/net80211/ieee80211_rssadapt.h 178354 2008-04-20 20:35:46Z sam $ */
3 /* $NetBSD: ieee80211_rssadapt.h,v 1.4 2005/02/26 22:45:09 perry Exp $ */
5 * Copyright (c) 2003, 2004 David Young. All rights reserved.
7 * Redistribution and use in source and binary forms, with or
8 * without modification, are permitted provided that the following
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials provided
15 * with the distribution.
16 * 3. The name of David Young may not be used to endorse or promote
17 * products derived from this software without specific prior
20 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY
21 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
23 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL David
24 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
26 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
28 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
33 #ifndef _NET80211_IEEE80211_RSSADAPT_H_
34 #define _NET80211_IEEE80211_RSSADAPT_H_
36 /* Data-rate adaptation loosely based on "Link Adaptation Strategy
37 * for IEEE 802.11 WLAN via Received Signal Strength Measurement"
38 * by Javier del Prado Pavon and Sunghyun Choi.
41 /* Buckets for frames 0-128 bytes long, 129-1024, 1025-maximum. */
42 #define IEEE80211_RSSADAPT_BKTS 3
43 #define IEEE80211_RSSADAPT_BKT0 128
44 #define IEEE80211_RSSADAPT_BKTPOWER 3 /* 2**_BKTPOWER */
46 struct ieee80211_rssadapt {
47 struct ieee80211vap *vap;
48 int interval; /* update interval (ticks) */
51 struct ieee80211_rssadapt_node {
52 struct ieee80211_rssadapt *ra_rs; /* backpointer */
53 struct ieee80211_rateset ra_rates; /* negotiated rates */
54 int ra_rix; /* current rate index */
55 int ra_ticks; /* time of last update */
56 int ra_last_raise; /* time of last rate raise */
57 int ra_raise_interval; /* rate raise time threshold */
59 /* Tx failures in this update interval */
61 /* Tx successes in this update interval */
63 /* exponential average packets/second */
65 /* RSSI threshold for each Tx rate */
66 uint16_t ra_rate_thresh[IEEE80211_RSSADAPT_BKTS]
67 [IEEE80211_RATE_SIZE];
70 void ieee80211_rssadapt_init(struct ieee80211_rssadapt *,
71 struct ieee80211vap *, int);
72 void ieee80211_rssadapt_cleanup(struct ieee80211_rssadapt *);
73 void ieee80211_rssadapt_setinterval(struct ieee80211_rssadapt *, int);
74 void ieee80211_rssadapt_node_init(struct ieee80211_rssadapt *,
75 struct ieee80211_rssadapt_node *, struct ieee80211_node *);
76 int ieee80211_rssadapt_choose(struct ieee80211_node *,
77 struct ieee80211_rssadapt_node *, u_int);
79 /* NB: these are public only for the inline below */
80 void ieee80211_rssadapt_raise_rate(struct ieee80211_rssadapt_node *,
81 int pktlen, int rssi);
82 void ieee80211_rssadapt_lower_rate(struct ieee80211_rssadapt_node *,
83 int pktlen, int rssi);
85 #define IEEE80211_RSSADAPT_SUCCESS 1
86 #define IEEE80211_RSSADAPT_FAILURE 0
89 ieee80211_rssadapt_tx_complete(struct ieee80211_rssadapt_node *ra,
90 int success, int pktlen, int rssi)
94 if ((ra->ra_rix + 1) < ra->ra_rates.rs_nrates &&
95 (ticks - ra->ra_last_raise) >= ra->ra_raise_interval)
96 ieee80211_rssadapt_raise_rate(ra, pktlen, rssi);
99 ieee80211_rssadapt_lower_rate(ra, pktlen, rssi);
102 #endif /* _NET80211_IEEE80211_RSSADAPT_H_ */