1 /* $OpenBSD: ieee80211_rssadapt.h,v 1.5 2010/07/17 16:25:09 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 * 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 28 * OF SUCH DAMAGE. 29 */ 30 #ifndef _NET80211_IEEE80211_RSSADAPT_H_ 31 #define _NET80211_IEEE80211_RSSADAPT_H_ 32 33 /* Data-rate adaptation loosely based on "Link Adaptation Strategy 34 * for IEEE 802.11 WLAN via Received Signal Strength Measurement" 35 * by Javier del Prado Pavon and Sunghyun Choi. 36 */ 37 38 /* Buckets for frames 0-128 bytes long, 129-1024, 1025-maximum. */ 39 #define IEEE80211_RSSADAPT_BKTS 3 40 #define IEEE80211_RSSADAPT_BKT0 128 41 #define IEEE80211_RSSADAPT_BKTPOWER 3 /* 2**_BKTPOWER */ 42 43 #define ieee80211_rssadapt_thresh_new \ 44 (ieee80211_rssadapt_thresh_denom - ieee80211_rssadapt_thresh_old) 45 #define ieee80211_rssadapt_decay_new \ 46 (ieee80211_rssadapt_decay_denom - ieee80211_rssadapt_decay_old) 47 #define ieee80211_rssadapt_avgrssi_new \ 48 (ieee80211_rssadapt_avgrssi_denom - ieee80211_rssadapt_avgrssi_old) 49 50 struct ieee80211_rssadapt_expavgctl { 51 /* RSS threshold decay. */ 52 u_int rc_decay_denom; 53 u_int rc_decay_old; 54 /* RSS threshold update. */ 55 u_int rc_thresh_denom; 56 u_int rc_thresh_old; 57 /* RSS average update. */ 58 u_int rc_avgrssi_denom; 59 u_int rc_avgrssi_old; 60 }; 61 62 struct ieee80211_rssadapt { 63 /* exponential average RSSI << 8 */ 64 u_int16_t ra_avg_rssi; 65 /* Tx failures in this update interval */ 66 u_int32_t ra_nfail; 67 /* Tx successes in this update interval */ 68 u_int32_t ra_nok; 69 /* exponential average packets/second */ 70 u_int32_t ra_pktrate; 71 /* RSSI threshold for each Tx rate */ 72 u_int16_t ra_rate_thresh[IEEE80211_RSSADAPT_BKTS] 73 [IEEE80211_RATE_SIZE]; 74 struct timeval ra_last_raise; 75 struct timeval ra_raise_interval; 76 }; 77 78 /* Properties of a Tx packet, for link adaptation. */ 79 struct ieee80211_rssdesc { 80 u_int id_len; /* Tx packet length */ 81 u_int id_rateidx; /* index into ni->ni_rates */ 82 struct ieee80211_node *id_node; /* destination STA MAC */ 83 u_int8_t id_rssi; /* destination STA avg RSS @ 84 * Tx time 85 */ 86 }; 87 88 void ieee80211_rssadapt_updatestats(struct ieee80211_rssadapt *); 89 void ieee80211_rssadapt_input(struct ieee80211com *, 90 const struct ieee80211_node *, struct ieee80211_rssadapt *, int); 91 void ieee80211_rssadapt_lower_rate(struct ieee80211com *, 92 const struct ieee80211_node *, struct ieee80211_rssadapt *, 93 const struct ieee80211_rssdesc *); 94 void ieee80211_rssadapt_raise_rate(struct ieee80211com *, 95 struct ieee80211_rssadapt *, const struct ieee80211_rssdesc *); 96 int ieee80211_rssadapt_choose(struct ieee80211_rssadapt *, 97 const struct ieee80211_rateset *, const struct ieee80211_frame *, 98 u_int, int, const char *, int); 99 #ifdef IEEE80211_DEBUG 100 extern int ieee80211_rssadapt_debug; 101 #endif /* IEEE80211_DEBUG */ 102 103 #endif /* _NET80211_IEEE80211_RSSADAPT_H_ */ 104