text: /*	$FreeBSD: head/sys/net80211/ieee80211_rssadapt.h 206358 2010-04-07 15:29:13Z rpaulo $	*/
  /* $NetBSD: ieee80211_rssadapt.h,v 1.4 2005/02/26 22:45:09 perry Exp $ */
  /*-
   * Copyright (c) 2003, 2004 David Young.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or
   * without modification, are permitted provided that the following
   * conditions are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above
   *    copyright notice, this list of conditions and the following
   *    disclaimer in the documentation and/or other materials provided
   *    with the distribution.
   * 3. The name of David Young may not be used to endorse or promote
   *    products derived from this software without specific prior
   *    written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
   * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL David
   * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
   * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
   * OF SUCH DAMAGE.
   */
  #ifndef _NET80211_IEEE80211_RSSADAPT_H_
  #define _NET80211_IEEE80211_RSSADAPT_H_
  
  /* Data-rate adaptation loosely based on "Link Adaptation Strategy
   * for IEEE 802.11 WLAN via Received Signal Strength Measurement"
   * by Javier del Prado Pavon and Sunghyun Choi.
   */
  
  /* Buckets for frames 0-128 bytes long, 129-1024, 1025-maximum. */
  #define	IEEE80211_RSSADAPT_BKTS		3
  #define IEEE80211_RSSADAPT_BKT0		128
  #define	IEEE80211_RSSADAPT_BKTPOWER	3	/* 2**_BKTPOWER */
  
  struct ieee80211_rssadapt {
  	const struct ieee80211vap *vap;
  	int	interval;			/* update interval (ticks) */
  };
  
  struct ieee80211_rssadapt_node {
  	struct ieee80211_rssadapt *ra_rs;	/* backpointer */
  	struct ieee80211_rateset ra_rates;	/* negotiated rates */
  	int	ra_rix;				/* current rate index */
  	int	ra_ticks;			/* time of last update */
  	int	ra_last_raise;			/* time of last rate raise */
  	int	ra_raise_interval;		/* rate raise time threshold */
  
  	/* Tx failures in this update interval */
  	uint32_t		ra_nfail;
  	/* Tx successes in this update interval */
  	uint32_t		ra_nok;
  	/* exponential average packets/second */
  	uint32_t		ra_pktrate;
  	/* RSSI threshold for each Tx rate */
  	uint16_t		ra_rate_thresh[IEEE80211_RSSADAPT_BKTS]
  					      [IEEE80211_RATE_SIZE];
  };
  
  #define	IEEE80211_RSSADAPT_SUCCESS	1
  #define	IEEE80211_RSSADAPT_FAILURE	0
  #endif /* _NET80211_IEEE80211_RSSADAPT_H_ */
  