Sec.  95.628   MICS transmitter.

   (a) Frequency monitoring. Medical implant programmer/control transmitters
   must incorporate a mechanism for monitoring the channel or channels that the
   MICS system devices intend to occupy. The monitoring system antenna shall be
   the antenna normally used by the programmer/control transmitter for a
   communications session. Before a medical implant programmer/control
   transmitter initiates a MICS communications session, the following access
   criteria must be met:

   (1) The monitoring system bandwidth measured at its 20 dB down points must
   be equal to or greater than the emission bandwidth of the intended
   transmission.

   (2) Within 5 seconds prior to initiating a communications session, circuitry
   associated with a medical implant programmer/control transmitter must
   monitor the channel or channels the MICS system devices intend to occupy for
   a minimum of 10 milliseconds per channel.

   (3) Based on use of an isotropic monitoring system antenna, the monitoring
   threshold power level must not be more than 10logB(Hz) − 150 (dBm/Hz) +
   G(dBi) where B is the emission bandwidth of the MICS communication session
   transmitter having the widest emission and G is the medical implant
   programmer/control transmitter monitoring system antenna gain relative to an
   isotropic antenna. For purposes of showing compliance with the above
   provision, the above calculated threshold power level must be increased or
   decreased by an amount equal to the monitoring system antenna gain above or
   below the gain of an isotropic antenna, respectively.

   (4) If no signal in a MICS channel above the monitoring threshold power
   level is detected, the medical implant programmer/control transmitter may
   initiate a MICS communications session involving transmissions to and from a
   medical implant device on that channel. The MICS communications session may
   continue as long as any silent period between consecutive data transmission
   bursts does not exceed 5 seconds. If a channel meeting the criteria in
   paragraph (a)(3) of this section is unavailable, the channel with the lowest
   ambient power level may be accessed.

   (5) When a channel is selected prior to a MICS communications session, it is
   permissible to select an alternate channel for use if communications is
   interrupted, provided that the alternate channel selected is the next best
   choice using the above criteria. The alternate channel may be accessed in
   the event a communications session is interrupted by interference. The
   following criteria must be met:

   (i) Before transmitting on the alternate channel, the channel must be
   monitored for a period of at least 10 milliseconds.

   (ii) The detected power level during this 10 millisecond or greater
   monitoring period must be no higher than 6 dB above the power level detected
   when the channel was chosen as the alternate channel.

   (iii) In the event that this alternate channel provision is not used by the
   MICS system or if the criteria in (i) and (ii) are not met, a channel must
   be selected using the access criteria specified in paragraphs (a)(1) through
   (a)(4) of this section.

   (6) As used in this section, the following definitions apply:

   (i) Emission bandwidth—Measured as the width of the signal between the
   points on either side of carrier center frequency that are 20 dB down
   relative to the maximum level of the modulated carrier. Compliance will be
   determined using instrumentation employing a peak detector function and a
   resolution bandwidth approximately equal to 1% of the emission bandwidth of
   the device under test.

   (ii) MICS channel—Any continuous segment of spectrum that is equal to the
   emission bandwidth of the device with the largest bandwidth that is to
   participate in a MICS communications session. (Note: The rules do not
   specify a channeling scheme for use by MICS systems.)

   (iii) MICS communications session—A collection of transmissions, that may or
   may not be continuous, between MICS system devices.

   (b) MICS communications sessions initiated by a medical implant event are
   not required to use the access criteria set forth in paragraph (a) of this
   section.

   (c) Stations may operate on any of the frequencies in the band 402–405 MHz,
   provided that the out-of-band emissions are attenuated in accordance with
    Sec. 95.635.

   (d) The authorized bandwidth of the emission from a MICS station shall not
   exceed 300 kHz, and no communications session involving MICS stations shall
   use more than a total of 300 kHz of bandwidth during such a session. Note:
   This provision does not preclude full duplex or half duplex communications
   provided that the total amount of bandwidth utilized by all of the MICS
   channels employed in such a MICS communications session does not exceed 300
   kHz.

   (e) Each transmitter in the MICS service must maintain a frequency stability
   of  ±100 ppm of the operating frequency over the range:

   (1) 25 °C to 45 °C in the case of medical implant transmitters; and

   (2) 0 °C to 55 °C in the case of medical implant programmer/control
   transmitters.

   (f) The provisions of this section shall not be used to extend the range of
   spectrum occupied over space or time for the purpose denying fair access to
   spectrum for other MICS systems.

   [ 64 FR 69930 , Dec. 15, 1999]