SiXMedical EXHIBIT 3-2D Message Timing & Duty Cycle (SAR)

FCC ID: CFS8DL6PNC

RF Exposure Info

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FCCID_3852340

2 Corporate Center Drive CFS8DL6MED / 573F-6MED Melville, NY 11747 516-577-2000 SiXMEDICAL Message Timing and Duty Cycle Calculation OVERVIEW The SiXMEDICAL and its Access Point (AP) use an 802.15.4-compliant message protocol which is similar to Zigbee on the physical level. In the RF6 device system, there will be one AP which will serve as the coordinator among all the sensor devices in the system. The AP generates a 5ms transmit ‘beacon’ every 245.76ms. The spacing between beacons is called a ‘’superframe’. A timing diagram of the superframe is provided on the following page. It can be referred to to locate the items described in this section. Within a superframe, the SiXMEDICAL and AP each has specific windows in which it is allowed to transmit. Outside of these windows, the device does not transmit. The SiXMEDICAL is a sensor device. Within a given superframe, a sensor device such as the SiXMEDICAL can only generate one of two response types: a device MAC response packet, or a 6LoWPAN response packet. The initial device MAC response packet is triggered by the beacon from the AP. Each sensor has a reserved time slot (based on its address) in which it is allowed to transmit its initial device MAC response packet. If this transmission is not received, the sensor will try to send the same packet at its next available opportunity, as described below. A device MAC response packet may contain alarm, status, or supervision information. In the same superframe, the sensor device may also generate up to 2 device MAC transmit retry messages. These may occur if the sensor device detects a collision upon sending its initial device MAC response packet (i.e. it does not receive an ACK from the AP). The response packet has two opportunities to be re-sent via a device MAC transmit retry message. The first opportunity is in a second time slot of the current superframe, shown in the timing diagram as Device MAC Response Transmit Retry Window 1. If this is not successful, the sensor will transmit the packet again in the next superframe, during the time window shown by Device MAC Response Transmit Retry Window 2. There is one 6LowPAN time slot available per superframe. The 6LoWPAN time slot is designated for transmission of Internet Protocol information only. With regard to this message, only one sensor is addressed by the AP in a 6LoWPAN transmit query. Only the sensor addressed may send a 6LowPAN response. There are no retry time windows for the sensor’s 6LoWPAN response; there is the initial opportunity only. PROTOCOL AND DATA RATE The SiXMEDICAL utilizes O-QPSK with DFSS modulation in the 2.4GHz band, with a 250kbps data rate. TIMING DIAGRAM A timing diagram is presented on the next page. DUTY FACTOR Duty factor calculations for SAR exclusion are on the pages following the timing diagram. Honeywell Internal Page 1 of 3

2 Corporate Center Drive CFS8DL6MED / 573F-6MED Melville, NY 11747 516-577-2000 TIMING DIAGRAM The Access Point (coordinator) generates beacon every 245.76ms (superframe). As shown in the figure, the duration of the beacon is 5ms. Superframe 245.76ms TRANSMISSIONS AP 6LoWPAN Request Post- ACCESS POINT Window Process 13.32 mS 194mS 51.76 mS 6LoWPAN 152 mS Tx 5ms 7.6 mS ACK ACK ACK ACK 5ms 0.4 mS 0.4 mS 0.4 mS 0.4 mS Beacon Beacon n+1 n 5ms 5ms 12.28 mS TRANSMISSIONS 42 mS SiXMEDICAL 78 mS 64ms 29.72 mS Device MAC response window 4.065 mS .250 uS and supervision window: 4 mS 1.6mS 250uS DATA 32 sensor devices, each gets a ACK 2ms slot. 1.6mS 1.6mS 0.4 mS 7.6 mS Device MAC Response Device MAC Response Packet Retry 2 Device MAC Response Packet Device 6LoWPAN Response Packet Packet Retry 1 30 bytes max. 30 bytes max. Time slot is function of sensor address and will ACK = 5 bytes, DATA = 128 bytes max. 30 bytes max. be positioned accordingly within the 64ms span depicted above. Device 6LoWPAN response to the Access Point responds with an ACK (depicted on Access Point 6LoWPAN Tx message from the access time axis). If ACK is missed by the sensor, it will retry this point (depicted on Access Point time transmission in Transmit Retry Window 1 of the this axis): Only the one device queried by 9.315mS superframe. the AP will reply. ACK and data are Beacon separated by 4mS processing. Syncronization Device MAC Response Retry Window 2 (5ms) Device MAC Response Retry Window 1 (5ms) This is a second retry window for a failed Device MAC This is a retry window for a failed Device MAC response Response Packet from the previous superframe, for which a Packet that occurred in this superframe. There is a 5ms the first retry during Device MAC Response Transmit Retry window in which this packet is allowed to be sent. The Window 1 of that superframe failed. There is a 5ms window Access Point responds with an ACK (depicted on Access in which this packet is allowed to be sent. The Access Point Point time axis). If an ACK is not detected from the AP, a responds with an ACK (depicted on Access Point time axis). second attempt to transmit this packet will be made in If an ACK is not detected from the AP, there will be no Device MAC Response Transmit Retry Window 2 of the next more transmit retries for this packet. superframe.. Honeywell Internal Page 2 of 3

2 Corporate Center Drive CFS8DL6MED / 573F-6MED Melville, NY 11747 516-577-2000 WORST CASE AVERAGE TRANSMIT TIME AS CALCULATED FOR SAR RULE PARTS This section shows the average SAR calculations for FCC and ISED using the transmit duty cycle. The duty cycle calculation for this purpose defines the time period as the full message cycle, as per FCC and ISED rules. The full message cycle is the same as the superframe, or 245.76ms. Per the manual and functional description, the device usage (and therefore, on-time) is limited to button pushes by the user under emergency conditions. In reality, a user can go days/weeks/months without having to initiate a transmission. Since the device sends a regular supervision signal once per hour, we will base our worse-case on-time assuming a user would initiate a transmission once every 3 seconds for a full hour. This shows the total amount of on-time one can expect to see in a one hour period, also taking into account the regular supervision signal. Referring to the timing diagrams on the previous pages, it is seen that all of the sensor’s RF6 transmissions are captured within a superframe: Device MAC Response Packet: 30 Bytes @ 250 kbps = ( 30 * 8 ) * ( 1 / [ 250*10^3 ] ) = 960 uS Device MAC Response Packet Retry 1: 30 Bytes @ 250 kbps = ( 30 * 8 ) * ( 1 / [ 250*10^3 ] ) = 960 uS Device MAC Response Packet Retry 2: 30 Bytes @ 250 kbps = ( 30 * 8 ) * ( 1 / [ 250*10^3 ] ) = 960 uS 6LoWPan Response Packet: 128 Bytes @ 250 kbps = ( 128 * 8 ) * ( 1 / [250*10^3 ] ) = 4096 uS Ack Message Packet: 5 bytes / Ack @ 250 kbps = ( 5 * 8 ) * ( 1 / [250*10^3 ] ) = 160 uS Transmit-on time per Single Button Push = [Device MAC Response Packet Retry 2] + [Device MAC Response Packet] + [ACK] + [6LoWPAN Response Packet] + [Device MAC Response Packet Retry 1] = 960uS + 960uS + 160uS + 4096uS + 960uS = 7136uS Regular Supervision Signal (once per hour) = 30 Bytes @ 250 kbps = ( 30 * 8 ) * ( 1 / [ 250*10^3 ] ) = 960 uS Thus, over a 1-hour period and at a rate of one button push every 3 seconds, one could expected a maximum of 1200 button pushes So the total expected on-time over a 1-hour window would be  (7136uS * 1200) + 960uS = 8564.16mS, or 8.564s This makes the duty factor, for purposes of calculating the SAR correction, equal to 8.564s/3600s, or 0.238%. This equates to a 10log(0.238/100), or –26.2 dB correction to determine average output power from burst power. The maximum rated conducted output power averaged over a 60 minute period becomes: 12.98dBm – 26.2dB = -13.3dBm, or 0.05mW This value is far below the 5mm distance threshold value of 10mW per the table “SAR Exclusion Threshold for 100MHz – 6GHz and ≤ 50mm” of Appendix A of KDB 447498 D01 General RF Exposure Guidance v06. As such, the SAR test exclusion is claimed. Honeywell Internal Page 3 of 3


Document Created: 2018-05-15 07:10:40
Document Modified: 2018-05-15 07:10:40
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