global_constant_c0 = 299792458; /* speed of light in m per s */
aktiv = window.setInterval("start()", 300);

function start()
{
  window.clearInterval(aktiv);
  calculate();
}

function roundto(val, c)
{
  if (c<=0) return Math.round(val);
  var d = Math.pow(10,c);
  var v = "" + (Math.round(val * d));
  var l = v.length;
  while (l <= c) { v = "0" + v; ++l; }
  return "" + v.substr(0, l-c) + "." + v.substr(l - c);
}

function log10(x)
{
  return Math.log(x)/Math.log(10);
}

function update_form(system, modulation)
{
  var color_disabled = "#b0b0b0";
  var color_enabled  = "black";

  /* disable pilotpatterns */
  for(var i = 0; i < document.dvbform.r_pp.length; ++i)
  {
    document.dvbform.r_pp[i].disabled = true;
    document.dvbform.r_pp[i].nextSibling.style.color = color_disabled;
  }
  document.dvbform.r_papr.disabled = true;
  document.dvbform.r_papr.nextSibling.style.color = color_disabled;

  /* disable bw's */
  for(var i = 0; i < document.dvbform.r_b.length; ++i)
  {
    document.dvbform.r_b[i].disabled = true;
    document.dvbform.r_b[i].nextSibling.style.color = color_disabled;
  }

  /* disable guards */
  for(var i = 0; i < document.dvbform.r_g.length; ++i)
  {
    document.dvbform.r_g[i].disabled = true;
    document.dvbform.r_g[i].nextSibling.style.color = color_disabled;
  }

  /* disable mode */
  for(var i = 0; i < document.dvbform.r_c.length; ++i)
  {
    document.dvbform.r_c[i].disabled = true;
    document.dvbform.r_c[i].nextSibling.style.color = color_disabled;
  }

  /* disable modulations */
  for(var i = 0; i < document.dvbform.r_m.length; ++i)
  {
    document.dvbform.r_m[i].disabled = true;
    document.dvbform.r_m[i].nextSibling.style.color = color_disabled;
  }

  document.getElementById("stream1").firstChild.data = String.fromCharCode(160);
  document.getElementById("stream2").firstChild.data = String.fromCharCode(160);

  /* disable hp coderates */
  for(var i = 0; i < document.dvbform.radio_coderate_hp.length; ++i)
  {
    document.dvbform.radio_coderate_hp[i].disabled = true;
    document.dvbform.radio_coderate_hp[i].nextSibling.style.color = color_disabled;
  }
  document.dvbform.r_mpe.disabled = true;
  document.dvbform.r_mpe.style.color = color_disabled;

  /* disable lp coderates */
  for(var i = 0; i < document.dvbform.radio_coderate_lp.length; ++i)
  {
    document.dvbform.radio_coderate_lp[i].disabled = true;
    document.dvbform.radio_coderate_lp[i].nextSibling.style.color = color_disabled;
  }

  if (system == "DVB-T")
  {
    /* enable some rf bandwidths */
    document.dvbform.r_b[2].disabled = false;
    document.dvbform.r_b[3].disabled = false;
    document.dvbform.r_b[4].disabled = false;
    document.dvbform.r_b[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_b[3].nextSibling.style.color = color_enabled;
    document.dvbform.r_b[4].nextSibling.style.color = color_enabled;

    /* enable some guard intervall values */
    document.dvbform.r_g[0].disabled = false;
    document.dvbform.r_g[2].disabled = false;
    document.dvbform.r_g[4].disabled = false;
    document.dvbform.r_g[5].disabled = false;
    document.dvbform.r_g[0].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[4].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[5].nextSibling.style.color = color_enabled;

    /* enable some cofdm modes */
    document.dvbform.r_c[1].disabled = false;
    document.dvbform.r_c[3].disabled = false;
    document.dvbform.r_c[1].nextSibling.style.color = color_enabled;
    document.dvbform.r_c[3].nextSibling.style.color = color_enabled;

    /* enable some modulation */
    document.dvbform.r_m[0].disabled = false;
    document.dvbform.r_m[1].disabled = false;
    document.dvbform.r_m[2].disabled = false;
    document.dvbform.r_m[4].disabled = false;
    document.dvbform.r_m[5].disabled = false;
    document.dvbform.r_m[0].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[1].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[4].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[5].nextSibling.style.color = color_enabled;

    /* enable some hp coderates */
    document.dvbform.radio_coderate_hp[0].disabled = false;
    document.dvbform.radio_coderate_hp[2].disabled = false;
    document.dvbform.radio_coderate_hp[3].disabled = false;
    document.dvbform.radio_coderate_hp[5].disabled = false;
    document.dvbform.radio_coderate_hp[6].disabled = false;
    document.dvbform.radio_coderate_hp[0].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[2].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[3].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[5].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[6].nextSibling.style.color = color_enabled;

    if (modulation == "QPSK+16QAM" || modulation == "QPSK+64QAM")
    {
      document.getElementById("stream1").firstChild.data = "robust/HP";
      document.getElementById("stream2").firstChild.data = "sensitive/LP";

      /* enable lp coderates */
      for(var i = 0; i < document.dvbform.radio_coderate_lp.length; ++i)
      {
        document.dvbform.radio_coderate_lp[i].disabled = false;
        document.dvbform.radio_coderate_lp[i].nextSibling.style.color = color_enabled;
      }
    }
  }
  else if (system == "DVB-H")
  {
    /* enable some rf bandwidths */
    document.dvbform.r_b[1].disabled = false;
    document.dvbform.r_b[2].disabled = false;
    document.dvbform.r_b[3].disabled = false;
    document.dvbform.r_b[4].disabled = false;
    document.dvbform.r_b[1].nextSibling.style.color = color_enabled;
    document.dvbform.r_b[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_b[3].nextSibling.style.color = color_enabled;
    document.dvbform.r_b[4].nextSibling.style.color = color_enabled;

    /* enable some guard intervall values */
    document.dvbform.r_g[0].disabled = false;
    document.dvbform.r_g[2].disabled = false;
    document.dvbform.r_g[4].disabled = false;
    document.dvbform.r_g[5].disabled = false;
    document.dvbform.r_g[0].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[4].nextSibling.style.color = color_enabled;
    document.dvbform.r_g[5].nextSibling.style.color = color_enabled;

    /* enable some cofdm modes */
    document.dvbform.r_c[1].disabled = false;
    document.dvbform.r_c[2].disabled = false;
    document.dvbform.r_c[3].disabled = false;
    document.dvbform.r_c[1].nextSibling.style.color = color_enabled;
    document.dvbform.r_c[2].nextSibling.style.color = color_enabled;
    document.dvbform.r_c[3].nextSibling.style.color = color_enabled;

    /* enable some modulation */
    document.dvbform.r_m[0].disabled = false;
    document.dvbform.r_m[1].disabled = false;
    document.dvbform.r_m[2].disabled = false;
    document.dvbform.r_m[0].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[1].nextSibling.style.color = color_enabled;
    document.dvbform.r_m[2].nextSibling.style.color = color_enabled;

    /* enable some hp coderates */
    document.dvbform.radio_coderate_hp[0].disabled = false;
    document.dvbform.radio_coderate_hp[2].disabled = false;
    document.dvbform.radio_coderate_hp[3].disabled = false;
    document.dvbform.radio_coderate_hp[5].disabled = false;
    document.dvbform.radio_coderate_hp[6].disabled = false;
    document.dvbform.radio_coderate_hp[0].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[2].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[3].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[5].nextSibling.style.color = color_enabled;
    document.dvbform.radio_coderate_hp[6].nextSibling.style.color = color_enabled;

    document.dvbform.r_mpe.disabled = false;
    document.dvbform.r_mpe.nextSibling.style.color = color_enabled;
  }
  else if (system == "DVB-T2")
  {
    /* enable all pp */
    for(var i = 0; i < document.dvbform.r_pp.length; ++i)
    {
      document.dvbform.r_pp[i].disabled = false;
      document.dvbform.r_pp[i].nextSibling.style.color = color_enabled;
    }
    document.dvbform.r_papr.disabled = false;
    document.dvbform.r_papr.nextSibling.style.color = color_enabled;

    /* enable all rf bandwidths */
    for(var i = 0; i < document.dvbform.r_b.length; ++i)
    {
      document.dvbform.r_b[i].disabled = false;
      document.dvbform.r_b[i].nextSibling.style.color = color_enabled;
    }

    /* enable all guard intervall values */
    for(var i = 0; i < document.dvbform.r_g.length; ++i)
    {
      document.dvbform.r_g[i].disabled = false;
      document.dvbform.r_g[i].nextSibling.style.color = color_enabled;
    }

    /* enable all cofdm fft modes */
    for(var i = 0; i < document.dvbform.r_c.length; ++i)
    {
      document.dvbform.r_c[i].disabled = false;
      document.dvbform.r_c[i].nextSibling.style.color = color_enabled;
    }

    /* enable some modulation */
    for(var i = 0; i <= 3; ++i)
    {
      document.dvbform.r_m[i].disabled = false;
      document.dvbform.r_m[i].nextSibling.style.color = color_enabled;
    }

    /* enable some hp coderates */
    for(var i = 0; i <= 5; ++i)
    {
      document.dvbform.radio_coderate_hp[i].disabled = false;
      document.dvbform.radio_coderate_hp[i].nextSibling.style.color = color_enabled;
    }
  }
}

function DVBTx_Carriers(system, carriermode)
{
  var Carriers = new Object();
  Carriers["DVB-T"]  = new Object();
  Carriers["DVB-H"]  = new Object();
  Carriers["DVB-T2"] = new Object();
  Carriers["DVB-T"]["2k"]      = [ 1512, 1704];
  Carriers["DVB-T"]["8k"]      = [ 6048, 6816];
  Carriers["DVB-H"]["2k"]      = [ 1512, 1704];
  Carriers["DVB-H"]["4k"]      = [ 3024, 3408];
  Carriers["DVB-H"]["8k"]      = [ 6048, 6816];
  Carriers["DVB-T2"]["1k"]     = [  804,  852];
  Carriers["DVB-T2"]["2k"]     = [ 1602, 1704];
  Carriers["DVB-T2"]["4k"]     = [ 3234, 3408];
  Carriers["DVB-T2"]["8k"]     = [ 6498, 6816];
  Carriers["DVB-T2"]["8kext"]  = [ 6588, 6912];
  Carriers["DVB-T2"]["16k"]    = [13002,13632];
  Carriers["DVB-T2"]["16kext"] = [13276,13920];
  Carriers["DVB-T2"]["32k"]    = [26022,27264];
  Carriers["DVB-T2"]["32kext"] = [26572,27840];

  if (system in Carriers && carriermode in Carriers[system])
    return Carriers[system][carriermode];

  return Array(0,0);
}

/* symbol duration in us */
function DVBTx_SymbolDuration(system, carriermode)
{
  var Duration = new Object();
  Duration["DVB-T"]  = new Object();
  Duration["DVB-H"]  = new Object();
  Duration["DVB-T2"] = new Object();
  Duration["DVB-T"]["2k"]      =  2*112;
  Duration["DVB-T"]["8k"]      =  8*112;
  Duration["DVB-H"]["2k"]      =  2*112;
  Duration["DVB-H"]["4k"]      =  4*112;
  Duration["DVB-H"]["8k"]      =  8*112;
  Duration["DVB-T2"]["1k"]     =  1*112;
  Duration["DVB-T2"]["2k"]     =  2*112;
  Duration["DVB-T2"]["4k"]     =  4*112;
  Duration["DVB-T2"]["8k"]     =  8*112;
  Duration["DVB-T2"]["8kext"]  =  8*112;
  Duration["DVB-T2"]["16k"]    = 16*112;
  Duration["DVB-T2"]["16kext"] = 16*112;
  Duration["DVB-T2"]["32k"]    = 32*112;
  Duration["DVB-T2"]["32kext"] = 32*112;

  if (system in Duration && carriermode in Duration[system])
    return Duration[system][carriermode] * 1e-6;

  return 0;
}

function DVBT_EffectiveCoderate(system, modulation, form_innercoderate, form_innercoderate_lp, form_mpe)
{
  var EffCoderate = new Object();
  EffCoderate["1/2"] = 564/1224;
  EffCoderate["2/3"] = 752/1224;
  EffCoderate["3/4"] = 846/1224;
  EffCoderate["5/6"] = 940/1224;
  EffCoderate["7/8"] = 987/1224;

  var eff_coderate    = 0;
  var eff_coderate_lp = 0;

  if (system == "DVB-T" &&
      (modulation == "QPSK" ||
       modulation == "16QAM" ||
       modulation == "64QAM" ||
       modulation == "QPSK+16QAM" ||
       modulation == "QPSK+64QAM"))
  {
    if (form_innercoderate in EffCoderate)
      eff_coderate = EffCoderate[form_innercoderate];

    if (form_innercoderate_lp in EffCoderate)
      eff_coderate_lp = EffCoderate[form_innercoderate_lp];
  }
  else if (system == "DVB-H" &&
          (modulation == "QPSK" ||
           modulation == "16QAM" ||
           modulation == "64QAM"))
  {
    if (form_innercoderate in EffCoderate)
      eff_coderate = EffCoderate[form_innercoderate];

    if (form_mpe != 0)
      eff_coderate = eff_coderate * 191 / 255;
  }

  return Array(eff_coderate, eff_coderate_lp);
}

function DVBX_bitspersymbol(modulation)
{
  var BPS = new Object();
  BPS["QPSK"]       = 2;
  BPS["16QAM"]      = 4;
  BPS["QPSK+16QAM"] = 4;
  BPS["64QAM"]      = 6;
  BPS["QPSK+64QAM"] = 6;
  BPS["256QAM"]     = 8;

  if (modulation in BPS)
    return BPS[modulation];

  return 0;
}

function calc_maxspeed(system, carriermode, carrierdist_hz)
{
  var max_dopplershift = carrierdist_hz / 12;
  var maxspeeds = new Array();

  maxspeeds[0] = roundto( ((200e6+max_dopplershift)/200e6 - 1)*global_constant_c0*3.6, 0);
  maxspeeds[1] = roundto( ((500e6+max_dopplershift)/500e6 - 1)*global_constant_c0*3.6, 0);
  maxspeeds[2] = roundto( ((800e6+max_dopplershift)/800e6 - 1)*global_constant_c0*3.6, 0);
  maxspeeds[3] = roundto( ((1465e6+max_dopplershift)/1465e6 - 1)*global_constant_c0*3.6, 0);

  return maxspeeds;
}

function getSpeedInfo(maxspeeds)
{
  var nodes;

  nodes = document.createElement("span");
  nodes.appendChild(document.createTextNode("200MHz: " + (maxspeeds[0]>300?">300":maxspeeds[0]) + " km/h,"));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode("500MHz: " + (maxspeeds[1]>300?">300":maxspeeds[1]) + " km/h,"));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode("800MHz: " + (maxspeeds[2]>300?">300":maxspeeds[2]) + " km/h"));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode("1465MHz: " + (maxspeeds[3]>300?">300":maxspeeds[3]) + " km/h"));

  return nodes;
}

function getCapacityInfo(capacity)
{
  var nodes;

  nodes = document.createElement("span");
  nodes.appendChild(document.createTextNode("" + getCapacityVBR(capacity, 4.5e6, .15) + " Px @ MPEG2 Standard-TV or "));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode(getCapacityVBR(capacity, 3e6, .1) + " Px @ MPEG4 Standard-TV or "));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode(getCapacityVBR(capacity, 10e6, .05) + " Px @ MPEG4 HighDef-TV or "));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode(getCapacityCBR(capacity, 256e3) + " Px @ MPEG1-Layer2 Audio or "));
  nodes.appendChild(document.createElement("br"));
  nodes.appendChild(document.createTextNode(getCapacityCBR(capacity, 112e3) + " Px @ AAC Audio"));

  return nodes;
}

function getCapacityCBR(nettodata, one_channel_req)
{
  return Math.floor(nettodata / one_channel_req);
}

function getCapacityVBR(nettodata, one_channel_req, muxgain)
{
  var required = one_channel_req;
  var count = "0";

  for(remain = nettodata;
      remain >= required;
      remain -= required, ++count)
  {
    /* consider gain when multipled
       but not less than 2/3 of the required capacity for one channel */
    required = Math.max(one_channel_req * Math.pow(1+muxgain, -count), one_channel_req*2/3);
  }

  /* if remaining capacity is at least 75% of what is
     required, say we *may* add a further service  */
  if (remain >= required * .75)
  {
    if (count < 1)
      count = "maybe 1";
    else
      count = "" + count + "-" + (count+1);
  }

  return count;
}

function getNetworkConfiguration(system, modulation, innercoderate, innercoderate_lp, tg_as_distance)
{
  var s;

  if (tg_as_distance >= 60)
  {
    if (modulation == "QPSK" || modulation == "16QAM" || modulation == "QPSK+16QAM")
      s = "regional SFN, nationwide SFN";
    else if (modulation == "QPSK+64QAM" || modulation == "64QAM")
      s = "regional SFN";
    else
      s = "MFN (SFN not recommended due to sensitive modulation)";
  }
  else if (tg_as_distance >= 30)
  {
    if (modulation == "QPSK" || modulation == "16QAM" || modulation == "QPSK+16QAM" ||
        modulation == "QPSK+64QAM" || modulation == "64QAM")
      s = "local SFN, regional SFN";
    else
      s = "MFN (SFN not recommended due to sensitive modulation)";
  }
  else if (tg_as_distance >= 10)
  {
    if (modulation == "QPSK" || modulation == "16QAM" || modulation == "QPSK+16QAM" ||
        modulation == "QPSK+64QAM" || modulation == "64QAM")
      s = "MFN, local SFN";
    else
      s = "MFN (SFN not recommended due to sensitive modulation)";
  }
  else
  {
    s = "MFN";
  }

  return s;
}

function getReception(system, modulation, innercoderate, innercoderate_lp, mpe_active, maxspeeds)
{
  var s;
  var info_speed;

  var sensitiviness_hp = Math.pow(DVBX_bitspersymbol(modulation),2);
  var sensitiviness_lp = 0;

  if (modulation == "QPSK+16QAM")
  {
    sensitiviness_hp = Math.pow(DVBX_bitspersymbol("QPSK"),2);
    sensitiviness_lp = Math.pow(DVBX_bitspersymbol("QPSK"),2);
  }
  else if (modulation == "QPSK+64QAM")
  {
    sensitiviness_hp = Math.pow(DVBX_bitspersymbol("QPSK"),2);
    sensitiviness_lp = Math.pow(DVBX_bitspersymbol("16QAM"),2);
  }

  if (innercoderate == "1/2")
    sensitiviness_hp *= .625;
  else if (innercoderate == "3/5")
    sensitiviness_hp *= .8;
  else if (innercoderate == "3/4")
    sensitiviness_hp *= 1.67;
  else if (innercoderate == "4/5")
    sensitiviness_hp *= 2.5;
  else if (innercoderate == "5/6")
    sensitiviness_hp *= 4;
  else if (innercoderate == "7/8")
    sensitiviness_hp *= 6;

  if (innercoderate_lp == "1/2")
    sensitiviness_lp *= .625;
  else if (innercoderate_lp == "3/4")
    sensitiviness_lp *= 1.67;
  else if (innercoderate_lp == "5/6")
    sensitiviness_lp *= 4;
  else if (innercoderate_lp == "7/8")
    sensitiviness_lp *= 6;

  if (mpe_active != 0)
    sensitiviness_hp *= .4;

  if (system == "DVB-T2")
    sensitiviness_hp *= .6;

  if (maxspeeds[0] <= 30)
    info_speed = "";
  else if (maxspeeds[0] <= 80)
    info_speed = ", slow speed mobile (VHF)";
  else if (maxspeeds[0] <= 130)
    info_speed = ", mobile (VHF)";
  else if (maxspeeds[0] <= 200)
    info_speed = ", high speed mobile (VHF) or slow speed mobile (UHF)";
  else if (maxspeeds[1] <= 130)
    info_speed = ", high speed mobile (VHF) or mid speed mobile (UHF)";
  else
    info_speed = ", high speed mobile (VHF+UHF)";

  if (sensitiviness_hp <= 6.5)
    s = "fixed, portable" + info_speed;
  else if (sensitiviness_hp <= 16)
    s = "fixed, portable" + info_speed + " with diversity receivers";
  else if (sensitiviness_hp <= 27)
    s = "fixed, portable";
  else
    s = "fixed";

  return s;
}

function DVBT2_NettobitsPerFecframe(modulation, coderate)
{
  var NB = new Object();
  NB["1/2"] = 32208-80;
  NB["3/5"] = 38688-80;
  NB["2/3"] = 43040-80;
  NB["3/4"] = 48408-80;
  NB["4/5"] = 51648-80;
  NB["5/6"] = 53840-80;

  if (coderate in NB)
    return NB[coderate];

  return 0;
}

/* return Array of NDataP2, NP2, CData, NDataFC, */
function DVBT2_Cells(fft, pilotpattern, papr)
{
  var CELLS = new Object();
  CELLS["1k"]     = new Object();
  CELLS["2k"]     = new Object();
  CELLS["4k"]     = new Object();
  CELLS["8k"]     = new Object();
  CELLS["8kext"]  = new Object();
  CELLS["16k"]    = new Object();
  CELLS["16kext"] = new Object();
  CELLS["32k"]    = new Object();
  CELLS["32kext"] = new Object();

  CELLS["1k"]["TRCELLS"]      = 10;
  CELLS["1k"]["CDATA_P2"]     = 558;
  CELLS["1k"]["N_P2"]         = 16;
  CELLS["1k"]["PP1"]          = [764, 568]; /* CData, NDataFC */
  CELLS["1k"]["PP2"]          = [768, 710];
  CELLS["1k"]["PP3"]          = [798, 710];
  CELLS["1k"]["PP4"]          = [804, 780];
  CELLS["1k"]["PP5"]          = [818, 780];

  CELLS["2k"]["TRCELLS"]      = 18;
  CELLS["2k"]["CDATA_P2"]     = 1118;
  CELLS["2k"]["N_P2"]         = 8;
  CELLS["2k"]["PP1"]          = [1522, 1136];
  CELLS["2k"]["PP2"]          = [1532, 1420];
  CELLS["2k"]["PP3"]          = [1596, 1420];
  CELLS["2k"]["PP4"]          = [1602, 1562];
  CELLS["2k"]["PP5"]          = [1632, 1562];
  CELLS["2k"]["PP7"]          = [1646, 1632];

  CELLS["4k"]["TRCELLS"]      = 36;
  CELLS["4k"]["N_P2"]         = 4;
  CELLS["4k"]["CDATA_P2"]     = 2236;
  CELLS["4k"]["PP1"]          = [3084, 2272];
  CELLS["4k"]["PP2"]          = [3092, 2840];
  CELLS["4k"]["PP3"]          = [3228, 2840];
  CELLS["4k"]["PP4"]          = [3234, 3124];
  CELLS["4k"]["PP5"]          = [3298, 3124];
  CELLS["4k"]["PP7"]          = [3328, 3266];

  CELLS["8k"]["TRCELLS"]      = 72;
  CELLS["8k"]["CDATA_P2"]     = 4472;
  CELLS["8k"]["N_P2"]         = 2;
  CELLS["8k"]["PP1"]          = [6208, 4544];
  CELLS["8k"]["PP2"]          = [6214, 5680];
  CELLS["8k"]["PP3"]          = [6494, 5680];
  CELLS["8k"]["PP4"]          = [6498, 6248];
  CELLS["8k"]["PP5"]          = [6634, 6248];
  CELLS["8k"]["PP7"]          = [6698, 6532];
  CELLS["8k"]["PP8"]          = [6698,    0];

  CELLS["8kext"]["TRCELLS"]   = 72;
  CELLS["8kext"]["CDATA_P2"]  = 4472;
  CELLS["8kext"]["N_P2"]      = 2;
  CELLS["8kext"]["PP1"]       = [6296, 4608];
  CELLS["8kext"]["PP2"]       = [6298, 5760];
  CELLS["8kext"]["PP3"]       = [6584, 5760];
  CELLS["8kext"]["PP4"]       = [6588, 6336];
  CELLS["8kext"]["PP5"]       = [6728, 6336];
  CELLS["8kext"]["PP7"]       = [6788, 6624];
  CELLS["8kext"]["PP8"]       = [6788,    0];

  CELLS["16k"]["TRCELLS"]     = 144;
  CELLS["16k"]["CDATA_P2"]    = 8944;
  CELLS["16k"]["N_P2"]        = 1;
  CELLS["16k"]["PP1"]         = [12418,  9088];
  CELLS["16k"]["PP2"]         = [12436, 11360];
  CELLS["16k"]["PP3"]         = [12988, 11360];
  CELLS["16k"]["PP4"]         = [13002, 12496];
  CELLS["16k"]["PP5"]         = [13272, 12496];
  CELLS["16k"]["PP6"]         = [13288, 13064];
  CELLS["16k"]["PP7"]         = [13416, 13064];
  CELLS["16k"]["PP8"]         = [13406,     0];

  CELLS["16kext"]["TRCELLS"]  = 144;
  CELLS["16kext"]["CDATA_P2"] = 8944;
  CELLS["16kext"]["N_P2"]     = 1;
  CELLS["16kext"]["PP1"]      = [12678,  9260];
  CELLS["16kext"]["PP2"]      = [12698, 11600];
  CELLS["16kext"]["PP3"]      = [13262, 11600];
  CELLS["16kext"]["PP4"]      = [13276, 12760];
  CELLS["16kext"]["PP5"]      = [13552, 12760];
  CELLS["16kext"]["PP6"]      = [13568, 13340];
  CELLS["16kext"]["PP7"]      = [13698, 13340];
  CELLS["16kext"]["PP8"]      = [13688,     0];

  CELLS["32k"]["TRCELLS"]     = 288;
  CELLS["32k"]["CDATA_P2"]    = 22432;
  CELLS["32k"]["N_P2"]        = 1;
  CELLS["32k"]["PP2"]         = [24886, 22720];
  CELLS["32k"]["PP4"]         = [26022, 24992];
  CELLS["32k"]["PP6"]         = [26592, 26128];
  CELLS["32k"]["PP7"]         = [26836,     0];
  CELLS["32k"]["PP8"]         = [26812,     0];

  CELLS["32kext"]["TRCELLS"]  = 288;
  CELLS["32kext"]["CDATA_P2"] = 22432;
  CELLS["32kext"]["N_P2"]     = 1;
  CELLS["32kext"]["PP2"]      = [25412, 23200];
  CELLS["32kext"]["PP4"]      = [26572, 25520];
  CELLS["32kext"]["PP6"]      = [27152, 26680];
  CELLS["32kext"]["PP7"]      = [27404,     0];
  CELLS["32kext"]["PP8"]      = [27376,     0];

  if  (fft in CELLS && pilotpattern in CELLS[fft])
  {
    if (papr)
    {
      return Array(CELLS[fft]["CDATA_P2"],
                   CELLS[fft]["N_P2"],
                   CELLS[fft][pilotpattern][0] - CELLS[fft]["TRCELLS"],
                   CELLS[fft][pilotpattern][1] - CELLS[fft]["TRCELLS"]);
    }
    return Array(CELLS[fft]["CDATA_P2"],
                 CELLS[fft]["N_P2"],
                 CELLS[fft][pilotpattern][0],
                 CELLS[fft][pilotpattern][1]);
  }
  return Array(0,0,0,0);
}

function DVBT2_MaxSymbolsPerFrame(fft, tguard)
{
  var MAXSYMBOLS = new Object();
  MAXSYMBOLS["1k"]     = new Object();
  MAXSYMBOLS["2k"]     = new Object();
  MAXSYMBOLS["4k"]     = new Object();
  MAXSYMBOLS["8k"]     = new Object();
  MAXSYMBOLS["8kext"]  = new Object();
  MAXSYMBOLS["16k"]    = new Object();
  MAXSYMBOLS["16kext"] = new Object();
  MAXSYMBOLS["32k"]    = new Object();
  MAXSYMBOLS["32kext"] = new Object();

  MAXSYMBOLS["1k"]["1/16"]       = 2098;
  MAXSYMBOLS["1k"][ "1/8"]       = 1982;
  MAXSYMBOLS["1k"][ "1/4"]       = 1784;

  MAXSYMBOLS["2k"]["1/32"]       = 1081;
  MAXSYMBOLS["2k"]["1/16"]       = 1049;
  MAXSYMBOLS["2k"][ "1/8"]       = 991;
  MAXSYMBOLS["2k"][ "1/4"]       = 892;

  MAXSYMBOLS["4k"]["1/32"]       = 540;
  MAXSYMBOLS["4k"]["1/16"]       = 524;
  MAXSYMBOLS["4k"][ "1/8"]       = 495;
  MAXSYMBOLS["4k"][ "1/4"]       = 446;

  MAXSYMBOLS["8k"][ "1/128"]     = 276;
  MAXSYMBOLS["8k"][  "1/32"]     = 270;
  MAXSYMBOLS["8k"][  "1/16"]     = 262;
  MAXSYMBOLS["8k"]["19/256"]     = 259;
  MAXSYMBOLS["8k"][   "1/8"]     = 247;
  MAXSYMBOLS["8k"]["19/128"]     = 242;
  MAXSYMBOLS["8k"][   "1/4"]     = 223;

  MAXSYMBOLS["8kext"][ "1/128"]  = 276;
  MAXSYMBOLS["8kext"][  "1/32"]  = 270;
  MAXSYMBOLS["8kext"][  "1/16"]  = 262;
  MAXSYMBOLS["8kext"]["19/256"]  = 259;
  MAXSYMBOLS["8kext"][   "1/8"]  = 247;
  MAXSYMBOLS["8kext"]["19/128"]  = 242;
  MAXSYMBOLS["8kext"][   "1/4"]  = 223;

  MAXSYMBOLS["16k"][ "1/128"]    = 138;
  MAXSYMBOLS["16k"][  "1/32"]    = 135;
  MAXSYMBOLS["16k"][  "1/16"]    = 131;
  MAXSYMBOLS["16k"]["19/256"]    = 129;
  MAXSYMBOLS["16k"][   "1/8"]    = 123;
  MAXSYMBOLS["16k"]["19/128"]    = 121;
  MAXSYMBOLS["16k"][   "1/4"]    = 111;

  MAXSYMBOLS["16kext"][ "1/128"] = 138;
  MAXSYMBOLS["16kext"][  "1/32"] = 135;
  MAXSYMBOLS["16kext"][  "1/16"] = 131;
  MAXSYMBOLS["16kext"]["19/256"] = 129;
  MAXSYMBOLS["16kext"][   "1/8"] = 123;
  MAXSYMBOLS["16kext"]["19/128"] = 121;
  MAXSYMBOLS["16kext"][   "1/4"] = 111;

  MAXSYMBOLS["32k"][ "1/128"]    = 68;
  MAXSYMBOLS["32k"][  "1/32"]    = 66;
  MAXSYMBOLS["32k"][  "1/16"]    = 64;
  MAXSYMBOLS["32k"]["19/256"]    = 64;
  MAXSYMBOLS["32k"][   "1/8"]    = 60;
  MAXSYMBOLS["32k"]["19/128"]    = 60;

  MAXSYMBOLS["32kext"][ "1/128"] = 68;
  MAXSYMBOLS["32kext"][  "1/32"] = 66;
  MAXSYMBOLS["32kext"][  "1/16"] = 64;
  MAXSYMBOLS["32kext"]["19/256"] = 64;
  MAXSYMBOLS["32kext"][   "1/8"] = 60;
  MAXSYMBOLS["32kext"]["19/128"] = 60;

  if (fft in MAXSYMBOLS && tguard in MAXSYMBOLS[fft])
    return MAXSYMBOLS[fft][tguard];

  return 0;
}

function DVBT2_Ncells(mod)
{
  var NCELLS = new Object();
  NCELLS[  "QPSK"] = 32400;
  NCELLS[ "16QAM"] = 16200;
  NCELLS[ "64QAM"] = 10800;
  NCELLS["256QAM"] =  8100;

  if (mod in NCELLS)
    return NCELLS[mod];

  return 0;
}

function DVBx_CNratio(system, rf_bw, fft, modulation, fec, dvbh_mpe, dvbt2_pilotpattern, dvbt2_papr)
{
  /* all values: Bw=8MHz, no PAPR */
  var CNR = new Object();

  CNR["DVB-T"]  = new Object();
  CNR["DVB-T"][ "QPSK"] = new Object();
  CNR["DVB-T"]["16QAM"] = new Object();
  CNR["DVB-T"]["64QAM"] = new Object();
  CNR["DVB-T"]["QPSK+16QAM"] = new Object();
  CNR["DVB-T"]["QPSK+64QAM"] = new Object();
  CNR["DVB-T"][ "QPSK"]["1/2"] = [ 3.5,  4.1,  5.9]; /* AWGN, Rice, Rayleigh */
  CNR["DVB-T"][ "QPSK"]["2/3"] = [ 5.3,  6.1,  9.6];
  CNR["DVB-T"][ "QPSK"]["3/4"] = [ 6.3,  7.2, 12.4];
  CNR["DVB-T"][ "QPSK"]["5/6"] = [ 7.3,  8.5, 15.6];
  CNR["DVB-T"][ "QPSK"]["7/8"] = [ 7.9,  9.2, 17.5];
  CNR["DVB-T"]["16QAM"]["1/2"] = [ 9.3,  9.8, 11.8];
  CNR["DVB-T"]["16QAM"]["2/3"] = [11.4, 12.1, 15.3];
  CNR["DVB-T"]["16QAM"]["3/4"] = [12.6, 13.4, 18.1];
  CNR["DVB-T"]["16QAM"]["5/6"] = [13.8, 14.8, 21.3];
  CNR["DVB-T"]["16QAM"]["7/8"] = [14.4, 15.7, 23.6];
  CNR["DVB-T"]["64QAM"]["1/2"] = [13.8, 14.3, 16.4];
  CNR["DVB-T"]["64QAM"]["2/3"] = [16.7, 17.3, 20.3];
  CNR["DVB-T"]["64QAM"]["3/4"] = [18.2, 18.9, 23.0];
  CNR["DVB-T"]["64QAM"]["5/6"] = [19.4, 20.4, 26.2];
  CNR["DVB-T"]["64QAM"]["7/8"] = [20.2, 21.3, 28.6];
  CNR["DVB-T"]["QPSK+16QAM"]["1/2"] = [ 5.1,  5.6,  7.7, 13.5, 14.1, 15.9]; /* HP: AWGN, Rice, Rayleigh, LP: AWGN, Rice, Rayleigh, alpha=2 */
  CNR["DVB-T"]["QPSK+16QAM"]["2/3"] = [ 7.3,  8.0, 11.4, 15.3, 16.1, 19.5];
  CNR["DVB-T"]["QPSK+16QAM"]["3/4"] = [ 8.6,  9.5, 14.2, 16.3, 17.2, 22.4];
  CNR["DVB-T"]["QPSK+16QAM"]["5/6"] = [ NaN,  NaN,  NaN, 17.3, 18.5, 25.5];
  CNR["DVB-T"]["QPSK+16QAM"]["7/8"] = [ NaN,  NaN,  NaN, 17.9, 19.2, 28.2];
  CNR["DVB-T"]["QPSK+64QAM"]["1/2"] = [ 8.5,  9.1, 11.8, 15.5, 16.0, 18.1]; /* HP: AWGN, Rice, Rayleigh, LP: AWGN, Rice, Rayleigh, alpha=2 */
  CNR["DVB-T"]["QPSK+64QAM"]["2/3"] = [12.5, 13.1, 16.4, 17.6, 18.3, 21.6];
  CNR["DVB-T"]["QPSK+64QAM"]["3/4"] = [15.0, 15.6, 19.3, 18.8, 19.7, 24.4];
  CNR["DVB-T"]["QPSK+64QAM"]["5/6"] = [ NaN,  NaN,  NaN, 20.0, 21.1, 27.6];
  CNR["DVB-T"]["QPSK+64QAM"]["7/8"] = [ NaN,  NaN,  NaN, 20.7, 21.9, 29.7];

  CNR["DVB-H"]  = new Object();
  CNR["DVB-H"][ "QPSK"] = new Object();
  CNR["DVB-H"]["16QAM"] = new Object();
  CNR["DVB-H"]["64QAM"] = new Object();
  CNR["DVB-H"][ "QPSK"]["1/2"] = CNR["DVB-T"][ "QPSK"]["1/2"];
  CNR["DVB-H"][ "QPSK"]["2/3"] = CNR["DVB-T"][ "QPSK"]["2/3"];
  CNR["DVB-H"][ "QPSK"]["3/4"] = CNR["DVB-T"][ "QPSK"]["3/4"];
  CNR["DVB-H"][ "QPSK"]["5/6"] = CNR["DVB-T"][ "QPSK"]["5/6"];
  CNR["DVB-H"][ "QPSK"]["7/8"] = CNR["DVB-T"][ "QPSK"]["7/8"];
  CNR["DVB-H"]["16QAM"]["1/2"] = CNR["DVB-T"]["16QAM"]["1/2"];
  CNR["DVB-H"]["16QAM"]["2/3"] = CNR["DVB-T"]["16QAM"]["2/3"];
  CNR["DVB-H"]["16QAM"]["3/4"] = CNR["DVB-T"]["16QAM"]["3/4"];
  CNR["DVB-H"]["16QAM"]["5/6"] = CNR["DVB-T"]["16QAM"]["5/6"];
  CNR["DVB-H"]["16QAM"]["7/8"] = CNR["DVB-T"]["16QAM"]["7/8"];
  CNR["DVB-H"]["64QAM"]["1/2"] = CNR["DVB-T"]["64QAM"]["1/2"];
  CNR["DVB-H"]["64QAM"]["2/3"] = CNR["DVB-T"]["64QAM"]["2/3"];
  CNR["DVB-H"]["64QAM"]["3/4"] = CNR["DVB-T"]["64QAM"]["3/4"];
  CNR["DVB-H"]["64QAM"]["5/6"] = CNR["DVB-T"]["64QAM"]["5/6"];
  CNR["DVB-H"]["64QAM"]["7/8"] = CNR["DVB-T"]["64QAM"]["7/8"];

  CNR["DVB-T2"] = new Object();
  CNR["DVB-T2"][  "QPSK"] = new Object();
  CNR["DVB-T2"][ "16QAM"] = new Object();
  CNR["DVB-T2"][ "64QAM"] = new Object();
  CNR["DVB-T2"]["256QAM"] = new Object();
  CNR["DVB-T2"][  "QPSK"]["1/2"] = [ 0.8,  1.0,  1.8]; /* AWGN, Rice, Rayleigh */
  CNR["DVB-T2"][  "QPSK"]["3/5"] = [ 2.1,  2.4,  3.4];
  CNR["DVB-T2"][  "QPSK"]["2/3"] = [ 2.9,  3.3,  4.6];
  CNR["DVB-T2"][  "QPSK"]["3/4"] = [ 3.9,  4.3,  5.9];
  CNR["DVB-T2"][  "QPSK"]["4/5"] = [ 4.5,  5.0,  6.8];
  CNR["DVB-T2"][  "QPSK"]["5/6"] = [ 5.0,  5.6,  7.2];
  CNR["DVB-T2"][ "16QAM"]["1/2"] = [ 5.7,  6.1,  7.3];
  CNR["DVB-T2"][ "16QAM"]["3/5"] = [ 7.4,  7.7,  9.1];
  CNR["DVB-T2"][ "16QAM"]["2/3"] = [ 8.6,  8.9, 10.5];
  CNR["DVB-T2"][ "16QAM"]["3/4"] = [ 9.8, 10.3, 12.2];
  CNR["DVB-T2"][ "16QAM"]["4/5"] = [10.6, 11.1, 13.4];
  CNR["DVB-T2"][ "16QAM"]["5/6"] = [11.2, 11.8, 14.4];
  CNR["DVB-T2"][ "64QAM"]["1/2"] = [ 9.6, 10.0, 11.7];
  CNR["DVB-T2"][ "64QAM"]["3/5"] = [11.7, 12.1, 13.8];
  CNR["DVB-T2"][ "64QAM"]["2/3"] = [13.2, 13.6, 15.4];
  CNR["DVB-T2"][ "64QAM"]["3/4"] = [14.9, 15.3, 17.5];
  CNR["DVB-T2"][ "64QAM"]["4/5"] = [15.9, 16.4, 19.0];
  CNR["DVB-T2"][ "64QAM"]["5/6"] = [16.6, 17.2, 19.9];
  CNR["DVB-T2"]["256QAM"]["1/2"] = [12.8, 13.3, 15.4];
  CNR["DVB-T2"]["256QAM"]["3/5"] = [15.6, 16.0, 18.1];
  CNR["DVB-T2"]["256QAM"]["2/3"] = [17.5, 17.8, 20.0];
  CNR["DVB-T2"]["256QAM"]["3/4"] = [19.7, 20.2, 22.5];
  CNR["DVB-T2"]["256QAM"]["4/5"] = [21.1, 21.5, 24.2];
  CNR["DVB-T2"]["256QAM"]["5/6"] = [21.8, 22.3, 25.3];

  /* additional correction value */
  var add_cn = 0;

  /*  DVB-H MPE correction */
  if (system == "DVB-H")
  {
    if (!dvbh_mpe)
      ;
    else
      add_cn -= 3;
  }

  /* DVB-T2 PAPR and PP correction */
  else if (system == "DVB-T2")
  {
    PPCOR = new Object();
    PPCOR["1k"]     = new Object();
    PPCOR["2k"]     = new Object();
    PPCOR["4k"]     = new Object();
    PPCOR["8k"]     = new Object();
    PPCOR["8kext"]  = new Object();
    PPCOR["16k"]    = new Object();
    PPCOR["16kext"] = new Object();
    PPCOR["32k"]    = new Object();
    PPCOR["32kext"] = new Object();
    PPCOR["1k"]["PP1"] = .34;
    PPCOR["1k"]["PP2"] = .32;
    PPCOR["1k"]["PP3"] = .44;
    PPCOR["1k"]["PP4"] = .42;
    PPCOR["1k"]["PP5"] = .45;
    PPCOR["1k"]["PP7"] = .29;
    PPCOR["2k"]["PP1"] = .35;
    PPCOR["2k"]["PP2"] = .33;
    PPCOR["2k"]["PP3"] = .43;
    PPCOR["2k"]["PP4"] = .42;
    PPCOR["2k"]["PP5"] = .47;
    PPCOR["2k"]["PP7"] = .29;
    PPCOR["4k"]["PP1"] = .39;
    PPCOR["4k"]["PP2"] = .37;
    PPCOR["4k"]["PP3"] = .47;
    PPCOR["4k"]["PP4"] = .45;
    PPCOR["4k"]["PP5"] = .51;
    PPCOR["4k"]["PP7"] = .34;
    PPCOR["8k"]["PP1"] = .41;
    PPCOR["8k"]["PP2"] = .39;
    PPCOR["8k"]["PP3"] = .49;
    PPCOR["8k"]["PP4"] = .48;
    PPCOR["8k"]["PP5"] = .53;
    PPCOR["8k"]["PP7"] = .37;
    PPCOR["8k"]["PP8"] = .37;
    PPCOR["8kext"]["PP1"] = .41;
    PPCOR["8kext"]["PP2"] = .41;
    PPCOR["8kext"]["PP3"] = .5;
    PPCOR["8kext"]["PP4"] = .48;
    PPCOR["8kext"]["PP5"] = .52;
    PPCOR["8kext"]["PP7"] = .39;
    PPCOR["8kext"]["PP8"] = .38;
    PPCOR["16k"]["PP1"] = .41;
    PPCOR["16k"]["PP2"] = .38;
    PPCOR["16k"]["PP3"] = .49;
    PPCOR["16k"]["PP4"] = .47;
    PPCOR["16k"]["PP5"] = .52;
    PPCOR["16k"]["PP6"] = .49;
    PPCOR["16k"]["PP7"] = .33;
    PPCOR["16k"]["PP8"] = .35;
    PPCOR["16kext"]["PP1"] = .42;
    PPCOR["16kext"]["PP2"] = .38;
    PPCOR["16kext"]["PP3"] = .49;
    PPCOR["16kext"]["PP4"] = .47;
    PPCOR["16kext"]["PP5"] = .52;
    PPCOR["16kext"]["PP6"] = .49;
    PPCOR["16kext"]["PP7"] = .34;
    PPCOR["16kext"]["PP8"] = .35;
    PPCOR["32k"]["PP2"] = .37;
    PPCOR["32k"]["PP3"] = .48;
    PPCOR["32k"]["PP4"] = .45;
    PPCOR["32k"]["PP6"] = .48;
    PPCOR["32k"]["PP7"] = .33;
    PPCOR["32k"]["PP8"] = .35;
    PPCOR["32kext"]["PP2"] = .37;
    PPCOR["32kext"]["PP3"] = .48;
    PPCOR["32kext"]["PP4"] = .45;
    PPCOR["32kext"]["PP6"] = .48;
    PPCOR["32kext"]["PP7"] = .33;
    PPCOR["32kext"]["PP8"] = .35;

    if (fft in PPCOR && dvbt2_pilotpattern in PPCOR[fft])
      add_cn += PPCOR[fft][dvbt2_pilotpattern];
  }

  if (system in CNR &&
      modulation in CNR[system] &&
      fec in CNR[system][modulation])
  {
    for (var i in CNR[system][modulation][fec])
    {
      CNR[system][modulation][fec][i] += add_cn;
    }
    return CNR[system][modulation][fec];
  }

  /* otherwise: unknown or unsupported */
  return Array(NaN, NaN, NaN);
}

function DVBx_receptiondist(cn_arr, rf_bw)
{
  /* ground wave propagation curves:
    1kW, 200MHz and UHF, tx@150mHaat, field strength in dBuV/m, 50% location, 50% time */
  var dist_km = [10,15,20,25,30,40,50,70,100,150];
  var vhf_dBuVm  = [77.5,69,64,59,55,48,42.5,34,24,11.5];
  var uhf_dBuVm  = [77,68,61.5,56.5,52,44,38,27.5,17,4.5];
  var uhfL_dBuVm = [77,67,61,55,51,43,36,24,13,1];

  /* tx power rel. to 1kW */
  var txpwr_db1kW = new Object();
  txpwr_db1kW["vhf3"] = 10;
  txpwr_db1kW["uhf4"] = 17;
  txpwr_db1kW["uhf5"] = 18;
  txpwr_db1kW["uhfL"] = 10;

  /* man made noise */
  var mmn_db = new Object();
  mmn_db["vhf3"] = 2;
  mmn_db["uhf4"] = 0;
  mmn_db["uhf5"] = 0;
  mmn_db["uhfL"] = 0;

  /* buildung penetration loss */
  var penetrloss_db = new Object();
  penetrloss_db["vhf3"] = 9;
  penetrloss_db["uhf4"] = 8;
  penetrloss_db["uhf5"] = 8;
  penetrloss_db["uhfL"] = 8;

  /* height correction 10m -> 1.5m */
  var height_db = new Object();
  height_db["vhf3"] = 12;
  height_db["uhf4"] = 16;
  height_db["uhf5"] = 18;
  height_db["uhfL"] = 21;

  /* rec. noise figure */
  var recn_db = new Object();
  recn_db["vhf3"] = 7;
  recn_db["uhf4"] = 7;
  recn_db["uhf5"] = 7;
  recn_db["uhfL"] = 7;

  /* antenna gain [inhouse, portable, fixed] */
  var gain_dbd = new Object();
  gain_dbd["vhf3"] = [-2.2,-2.2,7];
  gain_dbd["uhf4"] = [0,0,10];
  gain_dbd["uhf5"] = [0,0,12];
  gain_dbd["uhfL"] = [0,0,15];

  /* feeder loss [inhouse, portable, fixed] */
  var feed_db = new Object();
  feed_db["vhf3"] = [0,0,2];
  feed_db["uhf4"] = [0,0,3];
  feed_db["uhf5"] = [0,0,5];
  feed_db["uhfL"] = [0,0,10];

  /* location correction (50% -> 95%, inhouse or outdoor) [inhouse, portable, fixed] */
  var location_db = new Object();
  location_db["vhf3"] = [10,9,9];
  location_db["uhf4"] = [13,9,9];
  location_db["uhf5"] = [13,9,9];
  location_db["uhfL"] = [13,9,9];

  return Array(
    calc_emed_dist(200e6, rf_bw, txpwr_db1kW["vhf3"], cn_arr[2], recn_db["vhf3"], mmn_db["vhf3"], penetrloss_db["vhf3"], height_db["vhf3"], gain_dbd["vhf3"][0],feed_db["vhf3"][0], location_db["vhf3"][0], dist_km, vhf_dBuVm),
    calc_emed_dist(200e6, rf_bw, txpwr_db1kW["vhf3"], cn_arr[2], recn_db["vhf3"], mmn_db["vhf3"], 0,                     height_db["vhf3"], gain_dbd["vhf3"][1],feed_db["vhf3"][1], location_db["vhf3"][1], dist_km, vhf_dBuVm),
    calc_emed_dist(200e6, rf_bw, txpwr_db1kW["vhf3"], cn_arr[1], recn_db["vhf3"], mmn_db["vhf3"], 0,                     0,                 gain_dbd["vhf3"][2],feed_db["vhf3"][2], location_db["vhf3"][2], dist_km, vhf_dBuVm),

    calc_emed_dist(500e6, rf_bw, txpwr_db1kW["uhf4"], cn_arr[2], recn_db["uhf4"], mmn_db["uhf4"], penetrloss_db["uhf4"], height_db["uhf4"], gain_dbd["uhf4"][0],feed_db["uhf4"][0], location_db["uhf4"][0], dist_km, uhf_dBuVm),
    calc_emed_dist(500e6, rf_bw, txpwr_db1kW["uhf4"], cn_arr[2], recn_db["uhf4"], mmn_db["uhf4"], 0,                     height_db["uhf4"], gain_dbd["uhf4"][1],feed_db["uhf4"][1], location_db["uhf4"][1], dist_km, uhf_dBuVm),
    calc_emed_dist(500e6, rf_bw, txpwr_db1kW["uhf4"], cn_arr[1], recn_db["uhf4"], mmn_db["uhf4"], 0,                     0,                 gain_dbd["uhf4"][2],feed_db["uhf4"][2], location_db["uhf4"][2], dist_km, uhf_dBuVm),

    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhf5"], cn_arr[2], recn_db["uhf5"], mmn_db["uhf5"], penetrloss_db["uhf5"], height_db["uhf5"], gain_dbd["uhf5"][0],feed_db["uhf5"][0], location_db["uhf5"][0], dist_km, uhf_dBuVm),
    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhf5"], cn_arr[2], recn_db["uhf5"], mmn_db["uhf5"], 0,                     height_db["uhf5"], gain_dbd["uhf5"][1],feed_db["uhf5"][1], location_db["uhf5"][1], dist_km, uhf_dBuVm),
    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhf5"], cn_arr[1], recn_db["uhf5"], mmn_db["uhf5"], 0,                     0,                 gain_dbd["uhf5"][2],feed_db["uhf5"][2], location_db["uhf5"][2], dist_km, uhf_dBuVm),

    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhfL"], cn_arr[2], recn_db["uhfL"], mmn_db["uhfL"], penetrloss_db["uhfL"], height_db["uhfL"], gain_dbd["uhfL"][0],feed_db["uhfL"][0], location_db["uhfL"][0], dist_km, uhfL_dBuVm),
    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhfL"], cn_arr[2], recn_db["uhfL"], mmn_db["uhfL"], 0,                     height_db["uhfL"], gain_dbd["uhfL"][1],feed_db["uhfL"][1], location_db["uhfL"][1], dist_km, uhfL_dBuVm),
    calc_emed_dist(800e6, rf_bw, txpwr_db1kW["uhfL"], cn_arr[1], recn_db["uhfL"], mmn_db["uhfL"], 0,                     0,                 gain_dbd["uhfL"][2],feed_db["uhfL"][2], location_db["uhfL"][2], dist_km, uhfL_dBuVm)

  );
}

function calc_emed_dist(freq, rf_bw, txpwr_db1kW, cnratio_db, recn_db,
                        mmn_db, penetrloss_db, height_db, gain_dbd,
                        feed_db, location_db, x, y)
{
  var freq_db = 20 * log10(freq);
  var bw_db   = 10 * log10(rf_bw);
  var e_med = cnratio_db + recn_db + bw_db + freq_db - gain_dbd - 218.907 + feed_db + mmn_db + location_db + height_db + penetrloss_db;

  /* Bandwidth correction to be added to the C/N value
     (all C/N values above are for 7.61MHz systems only) */
  var bwcorr = bw_db - 68.814;

  var d = find_x(x, y, e_med + bwcorr - txpwr_db1kW);
  return Array(e_med, d);
}

function find_x(x_vec, y_vec, y)
{
  var i = 0;
  for (; i < y_vec.length; ++i)
  {
    if (y >= y_vec[i]) break;
  }
  if (i == 0)
    return 5+0*x_vec[0];
  if (i >= y_vec.length)
    return x_vec[x_vec.length-1];

  /* linear interpolation */
  var m = (y_vec[i] - y_vec[i-1]) / (x_vec[i] - x_vec[i-1]);
  var n = y_vec[i] - m * x_vec[i];
  var x = (y - n) / m;
  return x;
}

/**********************************************************************/

/*
system           - "DVB-T",  "DVB-T2",  "DVB-H"
bw_mhz           - numeric, in MHz
fft              - "1k", "2k", "4k", "8k", "8kext", "16k", "16kext", "32k", "32kext"
guard            - "1/4" ... "19/256" ... "1/128"
mod              - "QPSK", "16QAM", "64QAM", "256QAM", "QPSK+16QAM", "QPSK+64QAM"
innercoderate    - "1/2" ... "2/3" ... "7/8"
innercoderate_lp - "1/2" ... "2/3" ... "7/8"
dvbh_mpe         - 0 / 1
dvbt2_pp         - "PP1" ... "PP4" ... "PP8"
dvbt2_trpapr     - 0 / 1
*/
function isFormValid(system, bw_mhz, fft, guard, mod, innercoderate, innercoderate_lp, dvbh_mpe, dvbt2_pp, dvbt2_trpapr)
{
  isInvalid = 0;

  // forbidden parameter:
  if ("DVB-T" == system)
  {
    isInvalid = (isInvalid || "19/128" == guard || "19/256" == guard || "1/128" == guard);
    isInvalid = (isInvalid || "1k" == fft || "4k" == fft || "8kext" == fft || "16k" == fft || "16kext" == fft || "32k" == fft || "32kext" == fft);
    isInvalid = (isInvalid || "3/5" == innercoderate || "4/5" == innercoderate);
    isInvalid = (isInvalid || "256QAM" == mod);
    isInvalid = (isInvalid || 5.3 > bw_mhz || 8 < bw_mhz);
  }
  else if ("DVB-H" == system)
  {
    isInvalid = (isInvalid || "19/128" == guard || "19/256" == guard || "1/128" == guard);
    isInvalid = (isInvalid || "1k" == fft || "8kext" == fft || "16k" == fft || "16kext" == fft || "32k" == fft || "32kext" == fft);
    isInvalid = (isInvalid || "3/5" == innercoderate || "4/5" == innercoderate);
    isInvalid = (isInvalid || "256QAM" == mod || "QPSK+16QAM" == mod || "QPSK+64QAM" == mod);
    isInvalid = (isInvalid || 4.3 > bw_mhz || 8 < bw_mhz);
  }
  else if ("DVB-T2" == system)
  {
    isInvalid = (isInvalid || "7/8" == innercoderate);
    isInvalid = (isInvalid || "QPSK+16QAM" == mod || "QPSK+64QAM" == mod);
  }
  return !isInvalid;
}

function calcDATA(system, bw_mhz, fft, guard, mod, innercoderate, innercoderate_lp, dvbh_mpe, dvbt2_pp, dvbt2_trpapr)
{
  var DATA = new Object();

  /* init */
  DATA["OK"]                       = 0;  /* ok / error (wrong input)  */
  DATA["T_SYMBOL"]                 = ""; /* in us with 3 digits */
  DATA["T_GUARD"]                  = ""; /* in us with 3 digits */
  DATA["TX_DIST"]                  = ""; /* in km with 1 digit */
  DATA["F_BWRF"]                   = ""; /* in MHz with 3 digits */
  DATA["F_CARRIER"]                = ""; /* in kHz with 3 digits */
  DATA["MAXSPEED"]                 = ""; /* HTML Nodes */
  DATA["R_SYMBOLS"]                = ""; /* in MSym/s with 3 digits */
  DATA["R_BRUTTO"]                 = ""; /* in MBit/s with 3 digits */
  DATA["R_NETTO"]                  = ""; /* in MBit/s with 3 digits */
  DATA["R_NETTO_INFO"]             = ""; /* textual */
  DATA["TXT_CAPACITY"]             = ""; /* HTML Nodes */
  DATA["TXT_NETTOPO"]              = ""; /* textual */
  DATA["TXT_RECPT"]                = ""; /* textual */
  DATA["TXT_CN"]                   = ""; /* in dB */
  DATA["TXT_MINFS_1"]              = ""; /* textual */
  DATA["TXT_MINFS_2"]              = "";
  DATA["TXT_MINFS_3"]              = "";
  DATA["TXT_MINFS_4"]              = "";
  DATA["TXT_MINFS_5"]              = "";
  DATA["TXT_MINFS_6"]              = "";
  DATA["TXT_MINFS_7"]              = "";
  DATA["TXT_MINFS_8"]              = "";
  DATA["TXT_MINFS_9"]              = "";
  DATA["TXT_COVINFO"]              = ""; /* textual */

  var valid = isFormValid(system, bw_mhz, fft, guard, mod, innercoderate, innercoderate_lp, dvbh_mpe, dvbt2_pp, dvbt2_trpapr);
  if (!valid)
  {
    return DATA;
  }

  /* calc */
  var data_brutto   = 0;
  var data_netto    = 0;
  var data_netto_hp = 0;
  var data_netto_lp = 0;
  var netto_info    = "";

  var t_usesymbol       = DVBTx_SymbolDuration(system, fft) * 8 / bw_mhz;
  var t_guard           = t_usesymbol * eval(guard);
  var carriers          = DVBTx_Carriers(system, fft);
  var data_carriers     = carriers[0];
  var all_carriers      = carriers[1];
  var rf_bw             = (all_carriers+1) / t_usesymbol;
  var global_symbolrate = data_carriers / t_usesymbol;

  if ("DVB-T" == system || "DVB-H" == system)
  {
    var coderates = DVBT_EffectiveCoderate(system, mod, innercoderate, innercoderate_lp, dvbh_mpe);
    var global_eff_coderate    = coderates[0];
    var global_eff_coderate_lp = coderates[1];

    data_brutto = global_symbolrate * DVBX_bitspersymbol(mod) / (1 + eval(guard));
    data_netto = data_brutto * global_eff_coderate;

    if (mod == "QPSK+16QAM" || mod == "QPSK+64QAM")
    {
      data_netto_hp = global_symbolrate * DVBX_bitspersymbol("QPSK") * global_eff_coderate / (1 + eval(guard));

      if (mod == "QPSK+16QAM")
        data_netto_lp = global_symbolrate * DVBX_bitspersymbol("QPSK")* global_eff_coderate_lp / (1 + eval(guard));
      else /* mod == "QPSK+64QAM") */
        data_netto_lp = global_symbolrate * DVBX_bitspersymbol("16QAM")* global_eff_coderate_lp / (1 + eval(guard));

      data_netto = data_netto_hp + data_netto_lp;
      netto_info = "(HP: " + roundto(data_netto_hp/1e6, 3) + String.fromCharCode(160) + "Mbit/s, " +
                    "LP: " + roundto(data_netto_lp/1e6, 3) + String.fromCharCode(160) + "Mbit/s)";
    }
  }
  else if ("DVB-T2" == system)
  {
    var t_p1 = 224e-6;
    var lf = DVBT2_MaxSymbolsPerFrame(fft, guard);
    var nettobits_per_fecframe = DVBT2_NettobitsPerFecframe(mod, innercoderate);
    var cells  = DVBT2_Cells(fft, dvbt2_pp, dvbt2_trpapr);
    var c_p2   = cells[0];
    var n_p2   = cells[1];
    var c_data = cells[2];
    var n_fc   = cells[3];
    var framclosing_used = (0 != n_fc);

    lf = Math.floor(lf * bw_mhz / 8); /* see chapter 8.3.1 */

    if (0 == lf || 0 == c_p2 || 0 == c_data || 0 == n_p2)
    {
      ;
    }
    else
    {
      var end_lf = Math.floor(lf * 1/2);
      var max_lf = lf;
      var max_netto = 0;
      var start_lf = -1;
      var start_netto = 0;
      var netto = 0;
      /* see DVB-T2 implementation guidelines, page 50/51 */
      /* we have to find the maximum data rate by decreasing lf by one each loop */
      for (; lf >= end_lf && lf >= 1; lf -= 1)
      {
        if ((fft=="32k" || fft=="32kext") && 0 != (lf % 2))
        {
          /* chapter 5.5 */
          continue;
        }

        var l_data = lf - n_p2;
        var k_post_ex_pad = 102 + 79 + 32;
        var n_post_fec_block = Math.ceil(k_post_ex_pad / 7032);
        var k_sig = Math.ceil(k_post_ex_pad / n_post_fec_block);
        var n_post_temp = k_sig + 9168 - Math.floor(6*(7032-k_sig)/5);
        var d_l1_pre = 1840;
        var f = (n_p2 == 1 ? 2 : n_p2);
        var d_l1_post = f * n_post_fec_block * Math.ceil(n_post_temp / (f*DVBX_bitspersymbol(mod)) );
        var d_l1 = d_l1_pre + d_l1_post;
        var c_total = 0;
        if (framclosing_used)
        {
          c_total = n_p2 * c_p2 + (l_data-1) * c_data + n_fc;
        }
        else
        {
          c_total = n_p2 * c_p2 + l_data * c_data;
        }

        var d_plp = c_total - d_l1;
        var n_b_max = Math.floor(d_plp / DVBT2_Ncells(mod));
        var T = (t_p1 + lf * (t_usesymbol + t_guard));
        netto = 188 * n_b_max * nettobits_per_fecframe / (187*T);

//      netto_info = "" + nettobits_per_fecframe + "/"+c_p2 + "/"+n_p2 + "/"+c_data + "/"+n_fc+":"+
//                   c_total+ "/"+d_plp+ "/"+n_b_max+ "/"+T;
        if (start_lf < 0)
        {
          start_netto = netto
          start_lf    = lf;
        }
        if (netto > max_netto)
        {
          max_netto = netto
          max_lf    = lf;
        }
        //netto_info = netto_info + ", " + lf;
      }
      data_netto  = max_netto;
      data_brutto = data_netto * 64800 / nettobits_per_fecframe;

      end_netto = netto;
      end_lf    = (lf+1);

      netto_info = "" + roundto(end_netto/1e6, 3) + "..." +
                        roundto(start_netto/1e6, 3)+" Mbit/s " +
                   "(" + end_lf + "..." + start_lf + " Symbols/Frame), "+
                   "Maximum was found at " + max_lf + " Symbols/Frame";
    }
  }

  if (isNaN(data_netto) || data_netto <= 1000)
  {
    return DATA;
  }

  var guardint_as_dist  = roundto(t_guard * global_constant_c0 / 1000, 1);
  var cnratio_db        = DVBx_CNratio(system, bw_mhz, fft, mod, innercoderate, dvbh_mpe, dvbt2_pp, dvbt2_trpapr);
  var maxspeeds         = calc_maxspeed(system, fft, 1/t_usesymbol);
  var receptioncond     = DVBx_receptiondist(cnratio_db, rf_bw);
  var nettopo           = getNetworkConfiguration(system, mod, innercoderate, innercoderate_lp, guardint_as_dist);
  var pref_rec          = getReception(system, mod, innercoderate, innercoderate_lp, dvbh_mpe, maxspeeds);

  /* output */
  DATA["T_SYMBOL"]  = "" + roundto(t_usesymbol * 1e6, 1) + " µs";
  DATA["T_GUARD"]   = "" + roundto(t_guard * 1e6, 1) + " µs";
  DATA["TX_DIST"]   = "" + guardint_as_dist + " km";
  DATA["F_BWRF"]    = "" + roundto(rf_bw / 1e6, 3) + " MHz";
  DATA["F_CARRIER"] = "" + roundto(1/(1000*t_usesymbol), 3) + " kHz";
  DATA["MAXSPEED"]  = getSpeedInfo(maxspeeds);
  DATA["R_SYMBOLS"] = "" + roundto(global_symbolrate / 1e6, 3) + " Msym/s";;
  DATA["R_BRUTTO"]  = "" + roundto(data_brutto/1e6,3) + " Mbit/s";
  DATA["R_NETTO"]   = "" + roundto(data_netto/1e6, 3) + " Mbit/s";
  DATA["R_NETTO_INFO"] = netto_info;
  DATA["TXT_CAPACITY"] = getCapacityInfo(data_netto);
  DATA["TXT_NETTOPO"]  = "" + nettopo;
  DATA["TXT_RECPT"]    = "" + pref_rec;

  if (isNaN(cnratio_db[0]))
  {
    DATA["TXT_CN"]      = "not implemented, yet";
    DATA["TXT_COVINFO"] = "not implemented, yet";
  }
  else
  {
    DATA["TXT_CN"] = "" + roundto(cnratio_db[2],1) + "dB" + String.fromCharCode(160) + "/ " +
                          roundto(cnratio_db[1],1) + "dB" + String.fromCharCode(160) + "/ " +
                          roundto(cnratio_db[0],1) + "dB";
    for (var i=0; i<12; ++i)
    {
      var emin = receptioncond[i][0];
      var dist = receptioncond[i][1];
      var ch = "";
      if (dist<10.0) {ch = "<"; dist = 10.0; }
      if (dist>100.0){ch = ">"; dist = 100.0;}
      DATA["TXT_MINFS_"+(i+1)] = roundto(emin,1) + "dBµV/m" +
                                 String.fromCharCode(160) + "/" + String.fromCharCode(160) +
                                 ch + roundto(dist,1) + "km";
    }

    if (cnratio_db.length > 3)
    {
      DATA["TXT_COVINFO"] = "Note: values for HP stream only (alpha=2)";
    }
  }
  DATA["OK"] = 1;

  return DATA;
}

/**********************************************************************/


function calculate()
{
  var data_brutto = 0;
  var data_netto = 0;
  var data_netto_hp = 0;
  var data_netto_lp = 0;

  /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     the following values are obtained directly from form:
     - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

  var system           = document.dvbform.system.value;
  var bw_mhz           = eval(document.dvbform.channelbw_mhz.value);
  var fft              = document.dvbform.fftmode.value;
  var guard            = document.dvbform.guardfraction.value;
  var mod              = document.dvbform.mod.value;
  var innercoderate    = document.dvbform.coderate.value;
  var innercoderate_lp = document.dvbform.coderate_lp.value;
  var dvbh_mpe         = (document.dvbform.r_mpe.checked == true ? 1 : 0);
  var dvbt2_pp         = document.dvbform.dvbt2_pp.value;
  var dvbt2_trpapr     = (document.dvbform.r_papr.checked == true ? 1 : 0);

  update_form(system, mod);

  /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     calculate some values from the settings and take them:
     - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

   var DATA = calcDATA(system, bw_mhz, fft, guard, mod, innercoderate, innercoderate_lp, dvbh_mpe, dvbt2_pp, dvbt2_trpapr);
   var isOK = (0 != DATA["OK"]);

  /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     output
     - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

  if (isOK)
  {
    document.getElementById("tuseable2").firstChild.data = DATA["T_SYMBOL"];
    document.getElementById("tguard2").firstChild.data   = DATA["T_GUARD"];
    document.getElementById("tguard2distance2").firstChild.data = DATA["TX_DIST"];
    document.getElementById("bwhf2").firstChild.data = DATA["F_BWRF"];
    document.getElementById("txc2").firstChild.data  = DATA["F_CARRIER"];
    document.getElementById("maxspeed").replaceChild(DATA["MAXSPEED"], document.getElementById("maxspeed").firstChild);
    document.getElementById("symrate2").firstChild.data     = DATA["R_SYMBOLS"];
    document.getElementById("useablerate2").firstChild.data = DATA["R_NETTO"];
    document.getElementById("useablerate2info").firstChild.data = DATA["R_NETTO_INFO"];
    document.getElementById("bruttorate2").firstChild.data  = DATA["R_BRUTTO"];
    document.getElementById("pxcapacity").replaceChild(DATA["TXT_CAPACITY"], document.getElementById("pxcapacity").firstChild);
    document.getElementById("networktopo").firstChild.data = DATA["TXT_NETTOPO"];
    document.getElementById("reception").firstChild.data   = DATA["TXT_RECPT"];
    document.getElementById("cnr").firstChild.data = DATA["TXT_CN"];
    for (var i=0; i<12; ++i)
    {
      document.getElementById("cov"+(i+1)).firstChild.data = DATA["TXT_MINFS_"+(i+1)];
    }
    document.getElementById("cov_info").firstChild.data = DATA["TXT_COVINFO"];
  }
  else
  {
    document.getElementById("tuseable2").firstChild.data   = String.fromCharCode(160);
    document.getElementById("tguard2").firstChild.data     = String.fromCharCode(160);
    document.getElementById("tguard2distance2").firstChild.data = String.fromCharCode(160);
    document.getElementById("bwhf2").firstChild.data       = String.fromCharCode(160);
    document.getElementById("maxspeed").replaceChild(document.createTextNode(""), document.getElementById("maxspeed").firstChild);
    document.getElementById("symrate2").firstChild.data    = String.fromCharCode(160);
    document.getElementById("bruttorate2").firstChild.data = "Unsupported parameter combination!";
    document.getElementById("useablerate2").firstChild.data= "Select another combination!";
    document.getElementById("useablerate2info").firstChild.data = String.fromCharCode(160);
    document.getElementById("txc2").firstChild.data        = String.fromCharCode(160);
    document.getElementById("pxcapacity").replaceChild(document.createTextNode(""), document.getElementById("pxcapacity").firstChild);
    document.getElementById("networktopo").firstChild.data = String.fromCharCode(160);
    document.getElementById("reception").firstChild.data   = String.fromCharCode(160);
    document.getElementById("cnr").firstChild.data         = String.fromCharCode(160);
    for (var i=0; i<12; ++i)
    {
      document.getElementById("cov"+(i+1)).firstChild.data = String.fromCharCode(160);
    }
    document.getElementById("cov_info").firstChild.data = String.fromCharCode(160);
  }
}