Microhard Systems HP900 OEM 900 MHz Spread Spectrum Wireless Module User Manual Operating Manual
Microhard Systems Inc OEM 900 MHz Spread Spectrum Wireless Module Operating Manual
User Manual
ii HP900 Operating Manual
Warranty
Microhard Systems Inc. warrants that each product will be free of defects in material and workmanship for a period of one (1)
year for its products. The warranty commences on the date the product is shipped by Microhard Systems Inc. Microhard Systems
Inc.’s sole liability and responsibility under this warranty is to repair or replace any product which is returned to it by the Buyer
and which Microhard Systems Inc. determines does not conform to the warranty. Product returned to Microhard Systems Inc. for
warranty service will be shipped to Microhard Systems Inc. at Buyer’s expense and will be returned to Buyer at Microhard
Systems Inc.’s expense. In no event shall Microhard Systems Inc. be responsible under this warranty for any defect which is
caused by negligence, misuse or mistreatment of a product or for any unit which has been altered or modified in any way. The
warranty of replacement shall terminate with the warranty of the product.
Warranty Disclaims
Microhard Systems Inc. makes no warranties of any nature of kind, expressed or implied, with respect to the hardware, software,
and/or products and hereby disclaims any and all such warranties, including but not limited to warranty of non-infringement,
implied warranties of merchantability for a particular purpose, any interruption or loss of the hardware, software, and/or product,
any delay in providing the hardware, software, and/or product or correcting any defect in the hardware, software, and/or product,
or any other warranty. The Purchaser represents and warrants that Microhard Systems Inc. has not made any such warranties to
the Purchaser or its agents MICROHARD SYSTEMS INC. EXPRESS WARRANTY TO BUYER CONSTITUTES
MICROHARD SYSTEMS INC. SOLE LIABILITY AND THE BUYER’S SOLE REMEDIES. EXCEPT AS THUS
PROVIDED, MICROHARD SYSTEMS INC. DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
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MICROHARD SYSTEMS INC. PRODUCTS ARE NOT DESIGNED OR INTENDED TO BE USED IN
ANY LIFE SUPPORT RELATED DEVICE OR SYSTEM RELATED FUNCTIONS NOR AS PART OF
ANY OTHER CRITICAL SYSTEM AND ARE GRANTED NO FUNCTIONAL WARRANTY.
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LIABLE OR RESPONSIBLE FOR ANY DAMAGE OR INJURY, MICROHARD SYSTEMS INC.'S LIABILITY
FOR ANYDAMAGES SHALL NOT EXCEED THE PROFIT REALIZED BY MICROHARD SYSTEMS INC.
ON THE SALE OR PROVISION OF THE HARDWARE TO THE CUSTOMER.
Proprietary Rights
The Buyer hereby acknowledges that Microhard Systems Inc. has a proprietary interest and intellectual property rights in the
Hardware, Software and/or Products. The Purchaser shall not (i) remove any copyright, trade secret, trademark or other evidence
of Microhard Systems Inc.’s ownership or proprietary interest or confidentiality other proprietary notices contained on, or in, the
Hardware, Software or Products, (ii) reproduce or modify any Hardware, Software or Products or make any copies thereof, (iii)
reverse assemble, reverse engineer or decompile any Software or copy thereof in whole or in part, (iv) sell, transfer or otherwise
make available to others the Hardware, Software, or Products or documentation thereof or any copy thereof, except in accordance
with this Agreement.
iii
HP900 Regulatory Requirements
PLEASE READ THIS SECTION CAREFULLY
WARNING:
To satisfy FCC RF exposure requirements for mobile transmitting devices, a separation distance of 35 cm or more should be maintained
between the antenna of this device and persons during device operation. To ensure compliance, operations at closer than this distance is
not recommended. The antenna used for this transmitter must not be co-located in conjunction with any other antenna or transmitter.
WARNING:
Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received including interference that may cause undesired operation.
WARNING:
Changes or modifications not expressly approved by Microhard Systems Inc. could void the user’s authority to operate the equipment.
This device has been tested with the antennas listed in Appendix A When integrated in OEM products, fixed antennas require
installation preventing end-users from replacing them with non-approved antennas. Antennas not listed in the tables must be tested to
comply with FCC Section 15.203 (unique antenna connectors) and Section 15.247 (emissions).
WARNING:
MAXIMUM EIRP
FCC Regulations allow up to 36 dBm equivalent isotropically radiated power (EIRP). Therefore, the sum of the transmitted power
(in dBm), the cabling loss and the antenna gain cannot exceed 36 dBm.
WARNING:
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the
FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This
equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined
by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following
measures:
—Reorient or relocate the receiving antenna.
—Increase the separation between the equipment and receiver.
—Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
—Consult the dealer or an experienced radio/TV technician for help.
WARNING:
This device contains license-exempt transmitter(s)/receiver(s) that comply with Innovation, Science and Economic Development
Canada’s license-exempt RSS(s). Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference, including interference that may cause undesired operation of the device.
WARNING:
EQUIPMENT LABELING
The FCC and IC numbers depend on the model of the radio module. Do NOT use the Marketing Name of the product but the Model
to distinguish the Certifications Numbers. This device has been modularly approved. The manufacturer, product name, and FCC
and Industry Canada identifiers of this product must appear on the outside label of the end-user equipment.
SAMPLE LABEL REQUIREMENT for Model: HP900:
Contains:
FCC ID: NS9HP900 IC : 3143A-HP900
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference,
and (2) this device must accept any interference
received including interference that may cause
undesired operation.
iv HP900 Operating Manual
Co-Location with Cellular Modems
FCC: The maximum calculated MPE ratio for the EUT with 3 dBi dipole antenna is 0.216 (evaluated at 35 cm), this
configuration can be co-located with other antennas provided the sum of the MPE ratios for all the other
simultaneous transmitting antennas incorporated in a host device is < 1.0 - 0.216 < 0.784. The following co-location
were evaluated for mobile configurations:
Industry Canada: The maximum calculated MPE ratio for the EUT with 3 dBi dipole antenna is 0.474 (evaluated
at 35 cm), this configuration can be co-located with other antennas provided the sum of the MPE ratios for all the
other simultaneous transmitting antennas incorporated in a host device is < 1.0 - 0.474 < 0.526. The following co-
location were evaluated for mobile configurations:
1) EUT with 3 dBi dipole antenna co-located with LTE Data Module LM940
(FCC ID RI7LM940, IC: 5131A-LM940)
2) EUT with 3 dBi dipole antenna co- located with LTE Data Module L850
( FCC ID ZMOL850GL, IC 21374-L850GL)
3) EUT with 3 dBi dipole antenna co- located with LTE Data Module SARA-R410M
( FCC ID XPY2AGQN4NNN, IC 8595A-2AGQN4NNN)
4) EUT with 3 dBi dipole antenna co- located with LTE Data Module LE910-NA-V2
( FCC ID RI7LE910NAV2, IC 5131A-LE910NAV2 )
v
Contents
Indemnification ......................................................................................................................................................................... ii
Proprietary Rights ................................................................................................................................................. ii
HP900 Regulatory Requirements ........................................................................................................................ iii
Co-Location with Cellular Modems .....................................................................................................................iv
CONTENTS ................................................................................................................................................................ V
2. GENERAL ........................................................................................................................................................... 1
2.0 PRODUCT OVERVIEW ........................................................................................................................................................ 1
2.1 OUTPUT POWER LEVEL ..................................................................................................................................................... 2
3. INSTALLATION ................................................................................................................................................. 3
3.0 OVERVIEW ....................................................................................................................................................................... 3
3.1 ESTIMATING THE GAIN MARGIN ....................................................................................................................................... 3
3.2 ANTENNAS AND CABLING ................................................................................................................................................. 5
3.2.1 PCB Requirements for Antenna Interface .............................................................................................................. 5
3.2.2 PCB Requirements for RF Transmission line design ............................................................................................. 5
3.2.3 Internal Cabling ...................................................................................................................................................... 8
3.2.4 Installing External Cables, Antennas and Lightning Arrestors ............................................................................... 9
1
2. General
2.0 Product Overview
The HP900 is a high-performance embedded wireless data transceiver.
Operating in the 902 - 928 MHz ISM band, this frequency-hopping spread-
spectrum module is capable of providing reliable wireless data transfer
between almost any type of equipment which uses an asynchronous serial
interface. The small-size and superior RF performance of this module make
it ideal for many applications.
While a pair of HP900 modules can link two terminal devices (“point-to-
point” operation); multiple modules can be used together to create a
network of various topologies, including “point-to-multipoint” and
“repeater” operation. Multiple independent networks can operate
concurrently, so it is possible for unrelated communications to take place in
the same or a nearby area without sacrificing privacy or reliability.
1.1 Features
Key features of the HP900 include:
◼ transmission within a public, license-exempt band of the radio
spectrum
1
– this means that it can be used without access fees
(such as those incurred by cellular airtime).
◼ a serial I/O data port with handshaking and hardware flow
control, allowing the HP900 to interface directly to any
equipment with an asynchronous serial interface.
◼ ease of installation and use – the HP900 module uses a subset
of standard AT style commands, very similar to those used by
traditional telephone line modems.
◼ all units in a system are physically identical, and can be
configured as a master, repeater or slave using the AT
command set. No hardware modifications are required
◼ 128 sets of user-selectable pseudo-random hopping patterns,
intelligently designed to offer the possibility of separately
operating multiple networks while providing security,
reliability and high tolerance to interference.
◼ encryption key with 65536 user-selectable values to maximize
security and privacy of communications.
◼ 32-bit of CRC error detection and auto re-transmit to provide
accuracy and reliability of data.
1
902-928 MHz, which is license-free within North America; may need to be factory-
configured differently for some countries.
2
◼ TDMA (time division multiple access) support, allowing
multi-slave access in point-to-point mode.
◼ roaming ability, allowing repeaters and slaves to re-
synchronize with a new master if the synchronization pulse
from the original master is lost.
While the typical application for the HP900 is to provide a short- to mid-
range wireless communications link between DTEs, it can be adapted to
almost any situation where an asynchronous serial interface is used and data
intercommunication is required.
2.1 Output Power Level
The Output Power Level determines at what power the HP900 transmits.
The HP900’s sensitive receiver can operate with very low power levels, so
it is recommended that the lowest power necessary is used; using excessive
power contributes to unnecessary “RF pollution”.
Ideally, you should test the communications performance between units
starting from a low power level and working upward until the RSSI is
sufficiently high and a reliable link is established. The conditions will vary
widely between applications, the output power settings can be calculated
based on following information.
• Transmitter antenna gain
• Cable loss
• Equivalent Isotropically Radiated Power (EIRP) requirement by FCC
Regulations
Power Setting = 36 – Antenna Gain – Cable Loss
The power setting must be no more than the above calculation value. Any
higher is a violation of FCC rules. See IMPORTANT warning below.
Table 1 Output Power
Power Setting
(dBm)
Approx. Output Power
(mW)
0
1
20
100
21
125
22
160
23
200
24
250
25
320
26
400
27
500
28
630
29
800
30
1000
Chapter3 Installation 3
3. Installation
3.0 Overview
The HP900 complies with FCC part 15 at the modular level for operation in
the license-free 902-928 MHz ISM band. This chapter provides guidelines
for installing and deploying equipment which incorporates the HP900
module.
3.1 Estimating the Gain Margin
Successful communication between HP900 modules is dependent on three
main factors:
• System Gain
• Path Loss
• Interference
System gain is a calculation in dB describing the performance to be
expected between a transmitter-receiver pair. The number can be calculated
based on knowledge of the equipment being deployed. The following four
factors make up a system gain calculation:
1. Transmitter power (user selectable)
2. Transmitter gain (transmitting antenna gain minus cabling loss between
the transmitting antenna and the HP900 module)
3. Receiver gain (Receiving antenna gain minus cabling loss between the
receiving antenna and the module)
4. Receiver sensitivity (Specified as -108dBm on the HP900 module)
In the following illustration, the transmitting antenna has a gain of 6 dB,
and the receiving antenna has a gain of 3 dB. The cable loss between the
module and the antenna is 2 dB on both the transmitting and receiving side.
Transmitter
30 dBm
Output Power
Receiver
Sensitivity =
-105 dBm
Cable Loss = 2 dB
Cable Loss = 2 dB
Antenna Gain = 6 dB
Antenna Gain = 3 dB
4 HP900 Operating Manual
Figure 1 Gain Calculation
The power level has been set to 30dBm (1W) on the transmitter, and the
receiver sensitivity for the HP900 is -108dBm.
System gain would be calculated to be:
30 - 2 + 6 + 3 - 2 + 108 = 143 dB.
Figure 2 System Deploying
When deploying your system, care must be taken to ensure the path loss
(reduction of signal strength from transmitter to receiver in dB) between
equipment does not exceed the system gain (140 dB in the above example).
It is recommended to design for a gain margin of at least 20 dB to ensure
reliable communication. Gain margin is the difference between system gain
and path loss. Referring to the same example, suppose the path loss is 100
dB, the gain margin would be 40 dB, which is more than adequate for
reliable communication.
Path loss is a very complicated calculation which mainly depends on the
terrain profile, and the height of the antennas off the ground.
The following table provides path loss numbers for varying antenna heights
and antenna separation: These numbers are real averages taken from rural
environments. They do not apply to urban, non-line-of-sight environments.
Table 2 Path Loss
Distance
(km)
Base Height
(m)
Mobile Height
(m)
Path Loss
(dB)
5
15
2.5
116.5
5
30
2.5
110.9
8
15
2.5
124.1
8
15
5
117.7
8
15
10
105
16
15
2.5
135.3
16
15
5
128.9
16
15
10
116.2
16
30
10
109.6
16
30
5
122.4
16
30
2.5
128.8
Base Height (m)
Mobile
Height
(m)
Distance (km)
HP900 Operating Manual 5
Once the equipment is deployed, you can verify the signal strength by
entering into Command Mode and reading Register S123. This register
provides the average signal strength in dBm. The minimum strength for
communication is roughly -108dBm. For consistent reliable
communication, you should try to deploy the equipment such that signal
strength exceeds -95dBm.
3.2 Antennas and Cabling
This section describes the recommended procedure for PCB design for the
Antenna Connector and installing cabling and antennas for use with the
HP900 module.
3.2.1 PCB Requirements for Antenna Interface
The HP900 provides an RF interface for connecting an external antenna
through a PCB pad (#45 RF_Antenna) for RF signal transmission and
reception. A PCB must be designed that incorporates a 50 Ω trace to a RP-
SMA connector for the HP900 to interface to an external antenna. A high
quality 50 Ω RF connector, such as a RP-SMA connector, provides proper
PCB-to RF-cable transition.
Proper transition between RF_Antenna pad and the application board PCB
must be provided by following the design guidelines for the layout of the
application PCB close to the RF_Antenna pad:
• On a multilayer board, the layer stack below the RF connection
should be free of digital lines
• Increase GND clearance around the RF_Antenna pad, on the top
layer of the PCB, to at least 250 μm up to adjacent pads metal
definition and up to 400 μm on the area below the module, to
reduce parasitic capacitance to ground.
• Add GND clearance on the buried metal layer below the
RF_Antenna pad if the top-layer to buried layer dielectric
thickness is below is below 200 μm, to reduce parasitic capacitance
to ground.
3.2.2 PCB Requirements for RF Transmission line design
Any RF transmission line, such as the ones from the RF_Antenna pad up
to the related antenna connector or up to the related internal antenna pad,
must be designed so that the characteristic impedance is as close as possible
to 50 Ω.
The following figures provide two examples of proper 50 Ω coplanar
waveguide designs. The first example is of a RF transmission line
implemented in a 4-layer PCB, and the second is an example of a RF
transmission line implemented in a 2-layer PCB.
6 HP900 Operating Manual
Example of 50 Ω coplanar waveguide transmission line for 4-layer PCB
Example of 50 Ω coplanar waveguide transmission line for 2-layer PCB
To achieve a 50Ω characteristic impedance, the width of the transmission
line must be chosen depending on:
• the thickness of the transmission line itself (e.g. 35 μm)
• the thickness of the dielectric material between the top layer and
the next inner layer implementing the ground plane (e.g. 270 μm
(4-Layer), 1510 μm(2-Layer))
• the dielectric constant of the dielectric material (e.g. dielectric
constant of the FR-4 dielectric material)
• the gap from the transmission line to the adjacent ground plane on
the same layer of the transmission line (e.g. 500 μm in 4 Layer,
400 μm in 2 Layer boards).
In Addition to the 50Ω impedance, the following guidelines are
recommended for transmission lines design:
• Minimize the transmission line length: the insertion loss should be
minimized as much as possible
• Add GND clearance on buried metal layers below any pad of
component present on the RF transmission lines, if top-layer to
buried layer dielectric thickness is below 200 μm, to reduce
parasitic capacitance to ground
HP900 Operating Manual 7
• The transmission lines width and spacing to GND must be uniform
and routed as smoothly as possible: avoid abrupt changes of width
and spacing to GND
• Add GND stitching vias around transmission lines
• Ensure solid metal connection of the adjacent metal layer on the
PCB stack-up to main ground layer, providing enough vias on the
adjacent metal layer
• Route RF transmission lines far from any noise source and from
any sensitive circuits
• Avoid stubs on the transmission lines
• Avoid signal routing in parallel to transmission lines or crossing
the transmission lines on buried metal layer
• Do not route microstrip lines below discrete component or other
mechanics placed on top layer
An example of proper RF circuit design is shown below. In this case, the
RF_Antenna pin is directly connected to SMA connectors by means of a
50Ω transmission line, with the recommended design layout.
8 HP900 Operating Manual
3.2.3 Internal Cabling
The most common method for installing the module is to run a cable from
the RPSMA antenna connector on the application PCB to a reverse TNC
bulkhead connector on the chassis of the equipment as shown in
Figure 3. This cable can be purchased from Microhard Systems.
Figure 3 Suggested Internal Cabling
Cable losses are negligible for the short piece used within the chassis.
Additional losses up to 0.5 dB may be present in the RPSMA and Reverse
TNC connections.
RG316 Cable
with RPSMA male
connector
and Reverse TNC
bulkhead
connector
Reverse TNC Connector
RPSMA female connector
(HP900 OEM module installed on an
application PCB designed to the requirements
contained within this document.)
HP900
HP900 Operating Manual 9
WARNING:
To satisfy FCC RF exposure
requirements for mobile
transmitting devices, a separation
distance of 35 cm or more should
be maintained between the
antenna of this device and
persons during device operation.
To ensure compliance, operations
at closer than this distance is not
recommended. The antenna used
for this transmitter must not be
co-located in conjunction with
any other antenna or transmitter.
WARNING:
Direct human contact with the
antenna is potentially unhealthy
when the HP900 is generating RF
energy. Always ensure that the
HP900 equipment is powered
down during installation.
WARNING:
Never work on an antenna
system when there is lightning in
the area.
3.2.4 Installing External Cables, Antennas and Lightning
Arrestors
Never work on an antenna system when there is lightning in the area.
Direct human contact with the antenna is potentially unhealthy when the
HP900 is generating RF energy. Always ensure that the HP900 equipment
is powered down during installation. At all times a distance of 35 cm must
be maintained between the antenna and any person when the device is in
operation.
Surge Arrestors
The most effective protection against lightning is to install two lightning
(surge) arrestors, one at the antenna, the other one at the interface with the
equipment. The surge arrestor grounding system should be fully
interconnected with the transmission tower and power grounding systems to
form a single, fully integrated ground circuit. Typically, both ports on surge
arrestors are N-female.
External Filter
Although the HP900 is capable of filtering out RF noise in most
environments, there are circumstances that require external filtering.
Paging towers and cellular base stations in close proximity to the HP900
antenna can desensitize the receiver. Microhard Systems’ external cavity
filter eliminates this problem. The filter has two N-female ports and should
be connected in line at the interface to the RF equipment.
Weatherproofing
RPSMA and RPTNC connectors are not weatherproof. All connectors
should be taped with rubber splicing tape (weatherproofing tape), and then
coated with a sealant.
Cabling
The following coax cables are recommended:
Table 3 Cable Loss
Cable
Loss (dB/100ft)
LMR 195
10.7
LMR 400
3.9
LMR 600
2.5
Factors to take into consideration when choosing a cable are:
• price;
• bend radius limitations (the lower performance cables generally can
bend more sharply)
• performance requirements; and,
• distance between the equipment and the antenna.
10 HP900 Operating Manual
WARNING:
MAXIMUM EIRP
FCC and IC Regulations allow
up to 36dBm effective
isotropically radiated power
(EIRP). Therefore, the sum of
the transmitted power (in dBm),
the cabling loss and the antenna
gain cannot exceed
36 dBm with respect to the
isotropic radiator.
WARNING:
The HP900 can only be used with
any antennas listed in Appendix
A.
WARNING:
Be careful with dBi vs dBd gains
on antenna specifications.
Antenna manufactures may not
clearly indicate the gain on the
antenna if it is dBd or dBi. Note
1dBd = 2.15dBi.
When installing the cable, always begin fastening at the top near the
antenna connector/surge arrestor. The cable must be supported at the top
with a hose clamp or wrap lock, and at 5 ft intervals down the length of the
tower. Over-tightening the fasteners will dent the cable and reduce
performance. If properly grounded surge arrestors are not installed at both
the top and the bottom of the cable, then the cable should be grounded to
the tower at these locations using a cable grounding kit. If the tower is non-
conductive, then a separate conductor, physically separate from the cable,
should be run down the tower.
Antenna
Before choosing an antenna, you should have some knowledge of the path
loss and the topology of the equipment. If the equipment is in a fixed
location and is to communicate with only one other unit also in a fixed
location, then a Yagi antenna is suitable. Choose a Yagi with enough gain
to ensure adequate gain margin. When deploying the Yagi, point the
antenna towards the intended target, ensuring the antenna elements are
perpendicular to the ground for vertical polarization.
In applications where there are multiple units that you must communicate
with or units, which are in motion, you may select an Omni-directional
antenna with appropriate gain.
See appendix A for a list of approved antennas that can be used with
the HP900 radio modem. If you require another type of antenna please
contact Microhard Systems Inc. The HP900 CANNOT be used with
any antenna that does not appear in Appendix A.
Microhard Systems Inc. can provide you with approved antennas to ensure
FCC and Industry Canada compliance.
FCC Regulations allow up to 36dBm effective isotropically radiated
power (EIRP). Therefore, the sum of the transmitted power (in dBm),
the cabling loss and the antenna gain cannot exceed 36dBm with
respect to the isotropic radiator.
EIRP is calculated as follows:
EIRP = Tx Power(dBm) - Cable/Connector Loss(dB) + Ant Gain(dBi)
Antenna Gains must be in dBi when calculating the 36dBm EIRP limit.
1dBd = 2.15dBi
Use the guidelines in the previous section for calculating cable and
connector losses. If cabling and connector losses are 2 dB, then the
maximum allowable gain of the antenna will be 8 dB.
Examples of Antenna and Power settings to maintain 36dBm EIRP
Antenna
Power Level
Minimum Cable / Loss
EIPR
8.15 dBi Omni
30dBm
25 feet LMR195 / 2.675dB
35.475dBm
12.5 dBi Patch
23dBm
10 feet LMR195 / 1.07dB
34.43dBm
14.15 dBi Yagi
21dBm
10 feet LMR400 / 0.39dB
34.76dBm
HP900 Operating Manual 11
Examples:
FCC and Industry Canada Regulations allow up to 36dBm effective
isotropically radiated power (EIRP). Therefore, the sum of the
transmitted power (in dBm), the cabling loss and the antenna gain
cannot exceed 36dBm with respect to the isotropic radiator.
Example 1)
What is the maximum power the HP900 can be set to comply with FCC
and IC given the following equipment given a Rubber Ducky Ant Gain
2dBi and no cable or connectors in the system?
Max EIRP 36dBm
Max TX power = EIRP – Ant Gain(dBi) + Cable/Connector loss (dB)
Ant Gain dBi = 2dBi
Max TX power = 36dBm – 2dBi + 0dB = 34dBm
We can set the modem to the maximum power setting of 30dBm.
Example 2)
What is the maximum power the HP900 can be set to comply with FCC
and IC given the following equipment given a Yagi Ant Gain 11dBd
and cable and connector loss of 4.5 dB?
Max EIRP 36dBm
Max TX power = EIRP – Ant Gain(dBi) + Cable/Connector loss (dB)
Ant Gain dBi = Ant Gain dBd + 2.15 dB
Yagi Gain (dBi) = 11 + 2.15 = 13.15dBi
Max TX power = 36dBm – 13.15dB + 4.5dB = 27.35dBm
We must round down
Hence Max TX power = 27dBm
Example 3)
What is the maximum power the HP900 can be set to comply with FCC
and IC given the following equipment given a Omni Ant Gain 6dBd
and cable and connector loss of 2.5 dB?
Max EIRP 36dBm
Max TX power = EIRP – Ant Gain(dBi) + Cable/Connector loss (dB)
Ant Gain dBi = Ant Gain dBd + 2.15 dB
Omni Gain (dBi) = 6 + 2.15 = 8.15dBi
Max TX power = 36dBm – 8.15dB + 2.5dB = 30.35dBm
Hence Max TX power = 30dBm
12 HP900 Operating Manual
A. Approved Antennas
This radio transmitter [IC: 3143A-HP900] has been approved by Innovation, Science and Economic Development Canada
to operate with the antenna types listed below, with the maximum permissible gain indicated. Antenna types not included in
this list that have a gain greater than the maximum gain indicated for any type listed are strictly prohibited for use with this
device.
Group
Part Number
Description
Rubber Ducky
MHS031000
3dBi, 900MHz Rubber Ducky Antenna RPTNC Swivel
MHS031070
3dBi, 900MHz Rubber Ducky Antenna Reverse SMA Swivel
MHS031080
3dBi, 900MHz Rubber Ducky Antenna Reverse SMA Straight
Puck Antennas
MHS035460
4dBi, Puck Antenna 700-960 MHz/1575-2700 MHz Mag Mount
MHS035480
4dBi, Puck Antenna Main and Div 700-960 MHz/1575-2700 MHz Mag Mount
MHS035470
4dBi, Puck Antenna Main and Div 700-960 MHz/1575-2700 MHz Permanent Mount
Yagi Antennas
MHS031311
6dBd, 900MHz Yagi Directional Antenna Antenex, RPTNC Pigtail
MHS031431
6.5dBd, 900MHz Yagi Directional Antenna Bluewave, RPTNC Pigtail
MHS031501
9dBd, 900MHz Yagi Directional Antenna Antenex, RPTNC Pigtail
MHS031441
10dBd, 900 MHz Yagi Directional Antenna Bluewave, RPTNC Pigtail
MHS031451
11dBd, 900 MHz Yagi Directional Antenna Bluewave, RPTNC Pigtail
Patch Antennas
MHS031440
8dBi 900 MHz Patch Antenna, RPTNC Pigtail
Omni Directional
MHS031251
3dBd, 900MHz Omni Directional Antenna Antenex, RPTNC Pigtail
MHS031461
3dBd, 900 MHz Omni Directional Antenna Bluewave, RPTNC Pigtail
MHS031321
6dBd, 900MHz Omni Directional Antenna Antenex, RPTNC Pigtail
MHS031471
6dBd, 900 MHz Omni Directional Antenna Bluewave, RPTNC Pigtail
WARNING:
Changes or modifications not expressly approved by Microhard Systems Inc. could void the user’s authority to operate
the equipment. This device has been tested with the antennas listed in Appendix A When integrated in OEM products,
fixed antennas require installation preventing end-users from replacing them with non-approved antennas. Antennas
not listed in the tables must be tested to comply with FCC Section 15.203 (unique antenna connectors) and Section
15.247 (emissions). Please Contact Microhard Systems Inc. if you need more information.
Industry Canada: This device has been designed to operate with the antennas listed above, and having a maximum gain
of 13.15 dBi. Antennas not included in this list or having a gain greater than 13.15 dBi are strictly prohibited for use
with this device. The required antenna impedance is 50 ohms. To reduce potential radio interference to other users, the
antenna type and its gain should be so chosen that the equivalent isotropically radiated power (EIRP) is not more than
that required for successful communication. This Class B digital apparatus complies with Canadian ICES-003.