1 /* $OpenBSD: ieee80211_rssadapt.h,v 1.4 2007/06/16 13:17:05 damien Exp $ */ 2 /* $NetBSD: ieee80211_rssadapt.h,v 1.3 2004/05/06 03:03:20 dyoung Exp $ */ 3 4 /*- 5 * Copyright (c) 2003, 2004 David Young. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or 8 * without modification, are permitted provided that the following 9 * conditions are met: 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 18 * written permission. 19 * 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 31 * OF SUCH DAMAGE. 32 */ 33 #ifndef _NET80211_IEEE80211_RSSADAPT_H_ 34 #define _NET80211_IEEE80211_RSSADAPT_H_ 35 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. 39 */ 40 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 */ 45 46 #define ieee80211_rssadapt_thresh_new \ 47 (ieee80211_rssadapt_thresh_denom - ieee80211_rssadapt_thresh_old) 48 #define ieee80211_rssadapt_decay_new \ 49 (ieee80211_rssadapt_decay_denom - ieee80211_rssadapt_decay_old) 50 #define ieee80211_rssadapt_avgrssi_new \ 51 (ieee80211_rssadapt_avgrssi_denom - ieee80211_rssadapt_avgrssi_old) 52 53 struct ieee80211_rssadapt_expavgctl { 54 /* RSS threshold decay. */ 55 u_int rc_decay_denom; 56 u_int rc_decay_old; 57 /* RSS threshold update. */ 58 u_int rc_thresh_denom; 59 u_int rc_thresh_old; 60 /* RSS average update. */ 61 u_int rc_avgrssi_denom; 62 u_int rc_avgrssi_old; 63 }; 64 65 struct ieee80211_rssadapt { 66 /* exponential average RSSI << 8 */ 67 u_int16_t ra_avg_rssi; 68 /* Tx failures in this update interval */ 69 u_int32_t ra_nfail; 70 /* Tx successes in this update interval */ 71 u_int32_t ra_nok; 72 /* exponential average packets/second */ 73 u_int32_t ra_pktrate; 74 /* RSSI threshold for each Tx rate */ 75 u_int16_t ra_rate_thresh[IEEE80211_RSSADAPT_BKTS] 76 [IEEE80211_RATE_SIZE]; 77 struct timeval ra_last_raise; 78 struct timeval ra_raise_interval; 79 }; 80 81 /* Properties of a Tx packet, for link adaptation. */ 82 struct ieee80211_rssdesc { 83 u_int id_len; /* Tx packet length */ 84 u_int id_rateidx; /* index into ni->ni_rates */ 85 struct ieee80211_node *id_node; /* destination STA MAC */ 86 u_int8_t id_rssi; /* destination STA avg RSS @ 87 * Tx time 88 */ 89 }; 90 91 void ieee80211_rssadapt_updatestats(struct ieee80211_rssadapt *); 92 void ieee80211_rssadapt_input(struct ieee80211com *, 93 const struct ieee80211_node *, struct ieee80211_rssadapt *, int); 94 void ieee80211_rssadapt_lower_rate(struct ieee80211com *, 95 const struct ieee80211_node *, struct ieee80211_rssadapt *, 96 const struct ieee80211_rssdesc *); 97 void ieee80211_rssadapt_raise_rate(struct ieee80211com *, 98 struct ieee80211_rssadapt *, const struct ieee80211_rssdesc *); 99 int ieee80211_rssadapt_choose(struct ieee80211_rssadapt *, 100 const struct ieee80211_rateset *, const struct ieee80211_frame *, 101 u_int, int, const char *, int); 102 #ifdef IEEE80211_DEBUG 103 extern int ieee80211_rssadapt_debug; 104 #endif /* IEEE80211_DEBUG */ 105 106 #endif /* _NET80211_IEEE80211_RSSADAPT_H_ */ 107