Optimization Strategy of Mobile Cellular Network based on

Customer Smartphone Penetration

Wawan Budi Setiawan and Dodie Tricahyono

Magister Management, Telkom University, Jalan Gegerkalong Hilir, Bandung, Indonesia

Keywords: 4G Network, IDT, TAM, Telkomsel, Indonesia.

Abstract: This research is to determine a relationship between 4G device penetration and network development in

Telkomsel, the biggest cellular operator in Indonesia. The framework is a combination of IDT (Innovation

Diffusion Theory) and TAM (Technology Acceptance Model). As a qualitative research methodology,

primary data is collected and processed based on interviews with some experts inside Telkomsel and also with

the customers. While secondary data taken from internal data analytic were using forty thousand customer’s

data sampling in the Jakarta and surrounding areas. This research found that some of the reason behind the

low penetration of 4G networks are: no subsidy in 4G devices and partnerships, not evenly device distribution,

customer’s perception that 4G devices are wasteful both the quota and the battery, also customers already felt

enough with 3G network speed. This research suggested the program for increasing 4G USIM penetration

include the initial distribution of all cards using USIM, mapping sites for customers other than 4G, campaign

through CTP (customer touch points) and dealer partners and outbound calls for customers with high ARPU.

1 INTRODUCTION

The development of mobile technology from one

generation to the next generation continues to rapidly

progress, starting from 1G, 2G, 3G and now it

implements 4G (LTE). Some countries even are

experimenting 5G technology. With this speed of

change, the cellular technology lifecycle is

decreasing. It makes a big challenge for telco operator

in exploiting the advantages of one technology before

other advance technology takes place. Telco operator

is facing pressures in reaching the targeted ROI from

the previous investment of existing and legacy

technology. On the other hand, the telco operator

cannot delay new investment in new technology

because of the sustainability issue.

Some of the advantages of 4G technology among

others: down link speed up to 300 Mbps and uplink

speed up to 75 Mbps, latency (delay in access) that is

pretty low of less than 30 milliseconds and supports

high-mobility. The presence and superiority of 4G

technology have spurred customers to access

broadband data usage. Based on Telkomsel internal

data, there is a significant increase in broadband data

usage as shown in Figure 1, although it has not

reached a maximum level. To be able to serve a large

number of customers, it requires a network that has

comprehensive coverage of services to remote areas

throughout Indonesia. Telkomsel continues to

develop its service coverage both 2G, 3G, and 4G

networks. Until the end of 2017, the number of BTS

was 160,000. The ability to build networks, especially

4G / LTE, is key to supporting the presence of

smartphones.

Figure 1. Telkomsel Data Broadband.

Source: Annual report Telkomsel (2017)

4G technology encourages device manufacturers

to continue to produce a variety of 4G-capable

devices at a more affordable price for the customers.

The operator is trying to boost the growth of

smartphone users in various ways. Based on XL

498

Setiawan, W. and Tricahyono, D.

Optimization Strategy of Mobile Cellular Network based on Customer Smartphone Penetration.

DOI: 10.5220/0008432904980505

In Proceedings of the 2nd Inter national Conference on Inclusive Business in the Changing World (ICIB 2019), pages 498-505

ISBN: 978-989-758-408-4

Axiata's annual report released in 2017, smartphone

penetration was reached 70% where the number of

customers reached 53.5 millionand smartphone users

amounted to 38.3 million. The market Meanwhile,

Telkomsel the biggest operator with 161.5 million

customers in July 2018 manages 60.4% of

smartphones devices, 18.4% of feature phones (non-

smartphone phones that have internet data access

capabilities) and 11.2% of basic phones (non-

smartphone phones that do not have data access

capabilities).

The requirement to be able to use 4G service is

sufficient 4G network and customers were using the

4G device with USIM Card 4G. The fact that 4G

networks development has been massively built

compared to 2G and 3G technologies, do not make

the 4G device usage penetration reach the optimal

number. Data as of July 2018, reported that the

penetration of 4G subscriber devices still reaches

42% and the use of USIM cards reaches 32%. Based

on this matter, this paper aims to investigate the

causes of 4G device usage not being maximized and

associated with how to optimize the 4G network to be

used by the customer. The innovation diffusion

theory (IDT) seems the right theory that can be used

to start with.

2 THEORICAL BACKGROUND

2.1 Innovation Diffusion Theory

The Innovation Diffusion Theory (IDT) emerged at

the beginning of the 20th century in 1903 which was

introduced by Gabriel Tarde, a French sociologist, by

making an S-shaped Diffusion Curve. The S curve

illustrates the relationship between

innovations/adopted by someone or a group of people

based on time (Roger, 2003). The more people who

contact with innovation, the more the rate of spread

increases. Eventually, so many members of the

community will be affected in adopting the

innovation.

According to (Roger, 2003: 5) the notion of

diffusion is "as the process of innovation is

communicated through certain channels over time

among the members of a social system". This

definition highlights four key words: innovation,

communication channels, time, and social system

(Sahin, 2006). Furthermore, in innovation, there are

five other variables, namely relative advantages,

complexity, compatibility, trialability and

observability (Roger, 2003).

2.2 Technology Acceptance Model

Technology Acceptance Model (TAM) is a behaviour

theory developed by Davis in 1986 (Indrawati, 2017).

It is used to measure why consumer attitudes and

beliefs can influence consumer behaviour in

accepting or rejecting a product. In TAM there are

two variables, namely perceived usefulness and

perceived ease to use. Perceived usefulness is defined

as the level of a person believes that he/she will

improve his/her performance by using a new

particular system. While perceived easy to use is

defined as the level a person believes that using the

particular new system is effortless (Davis, 1986).

Some previous research has combined between

the theory of IDT and TAM used in the study of

information technology (Chen, Gillensen, & Sherrel,

2002; Oh, Ahn, & Kim, 2003; Wu & Wang, 2005;

Min, Noh, & Ghee, 2018). For example, Min et al.

(2018) investigated the factor to influence the

intention to use smartwatches using the integrated

model of technology acceptance model (TAM) and

innovation diffusion technology (IDT). Based on the

previous research mentioned above, this paper

assumed, a combine between TAM and IDT can be

used to measure the penetration of smartphones as

describes in Figure 2.

Some variables in IDT which are part of the

variables perceived as attributes of innovation

(Roger, 2003) can be defined as:

a. Compatibility is the degree to which an

innovation is perceived as consistent with the

existing value, past experiences and need of

potential adopters.

b. Observability is the degree to which the result of

innovation is visible to others.

c. Trialability is the degree to which an innovation

may have experimented on a limited basis.

Figure 2 Combined IDT and TAM.

Source : J. Min, Y. Noh., Ghee. (2018).

3 METHODOLOGY

3.1 Research Character

Based on the problems and objectives that have been

determined, the research methodology used is a

Optimization Strategy of Mobile Cellular Network based on Customer Smartphone Penetration

499

qualitative method. Qualitative business research is

research conducted to business objectives through

techniques that enable researchers to present material

to interpret research phenomena without depending

on numerical measurements (Sugiyono, 2014).

This study has a focus on acquiring real meaning

and getting insights about problems and research

questions (Zikmund, Babin, Carr, & Graffin, 2010).

Qualitative research methods are often called

naturalistic research methods because their research

is carried out in natural settings (Sugiyono, 2014).

Based on the purpose, this study uses descriptive to

describe and explain the phenomenon that occurs and

look for answers to the research questions that has

been explained.

3.2 Data Collection and Measure

The primary data is obtained from in-depth interviews

with some informants from Telkomsel’s employees.

The informants are selected based on the employee’s

level of expertise that reflected by their position at the

managerial level. It includes vice president (VP) and

manager who understands the problem In addition,

this study also invites some customers who have been

using Telkomsel services for more than 5 years, but

they have not used 4G services. It is because either

their device is not 4G or has not used the 4G USIM

card. Interviews with participants were conducted

between November-December 2018.

Table 1. A sampling of questionnaire interviews.

Variable

Questionnaire

Perceived

Useful

Based on data penetration of 4G

devices only reached 42%, what are the

factors cause this to happen?

How are the strategies for increasing

4G device penetration?

Device usage is approaching

saturation. Why does this happen?

Perceived

Ease to Use

How easy is to use a 4G network and

plan ahead?

How easy are you to use the Telkomsel

network?

Compatibility

What is the compatibility between the

need for internet data access with a 3G

device and not replacing the 4G

device?

Observability

Have you ever observed 4G services

and what relative advantages did you

get?

Trialability

Have you ever tried a 4G device? And

what is your experience?

Source : Interviews data collecting

Interviews were audio-recorded at PT. Telkomsel

TSO (Telkomsel Smart Office) Building, South

Jakarta. The topic of interview was about exploring

some issues: (1) the cause of 4G Telkomsel handset

penetration has not reached 50%, (2) strategy to

increase 4G device penetration, (3) ease of using 4G

network, (4) conformity between the need for internet

data access with 3G devices, (5) observability and

trialability.

In order to understand the phenomenon better, the

secondary data was collected. Artefact in this study is

data sampling of 40 thousand customers in the Jakarta

and surrounding areas that use smartphones, feature

phone, and basic phones. Some parameters used in

this data collection are: MSISDN, Device Type,

USIM, Device. Secondary data was taken from

Telkomsel internal data on October 2018.

Validity test is done by: First, by using

triangulation process that combines several points of

view and methods. This triangulation process is done

by comparing several interviews that have been

conducted, both for the VP (vice president) level and

the manager level who have competence in the field

under study. Second, by implementing expert

validation. It involves key informants who have

detailed knowledge of ideas, concepts, and

relationships between concepts of phenomena that

exist in the research. Third, by using the credibility

test to make sure whether the views of respondents to

the results of research are in accordance with those

presented and reconstructed by researchers.

When data collection is done, data analysis takes

place. Analysis of answers to be delivered at the time

the interview is conducted before the interview

process takes place. If the answers submitted by the

informant at the time of the interview are not

satisfactory, then the research question will continue

to a certain extent until data that is deemed credible is

obtained. Miles and Huberman’s model (in Sugiyono,

2003) emphasizes the analytical activities carried out

interactively and continuously until the data is

saturated.

Activities in data analysis include data reduction,

data display, and conclusion. Before entering into

data reduction, researchers first carry out anticipatory

data reduction. Data reduction occurs when the

researcher decides which conceptual model is used,

the object to be studied, the research question to be

used, and the method of data collection to be used

(Sugiyono, 2014). Finally, conclusions are based on

the results of data reduction and combining with

previous information.

ICIB 2019 - The 2nd International Conference on Inclusive Business in the Changing World

500

4 RESULT

4.1 Secondary Data

The secondary data process in the Jakarta area shows

that 76% of customers had used smartphones and

57% were a 4G device capable. This is logic since the

Jakarta region has the highest economic level/level of

economic capacity compared to other regions. As the

most developed business area, information updates

are automatically as well as the need for access to

internet data usage in the Jakarta region is greater than

in other regions. Beside the development of cellular

infrastructure is the most mature compared to other

regions in Indonesia. Figure 3 shows the customers

data regarding the ownership of the device.

Table 2: Secondary Data Sampling.

Source : Telkomsel Internal Data

From 40 thousand customers, only 47% have used

USIM (4G sim card). It means that 4G customers’

USIM penetration has not been maximized. While for

4G device users who have used USIM cards is

15,379, while compared with the number of 40,000

customers, then those using 4G and USIM 4G devices

(15,379/40,000) are equal to 38.44%. This indicates

that Telkomsel customers that use 4G network

services in the Jakarta area are still relatively small.

Market is still available in the future. Information

from secondary data is the basic for interviews with

the participants to find out the cause of 4G penetration

is still relatively low.

Figure 3: % Device Penetration.

Source : Secondary Data Processing Result

Figure 4: USIM Penetration.

Source: Secondary Data Processing Result

4.2 Primary Data

Primary data is achieved by conducting interviews

with experts in Telkomsel internally. The participants

were selected based on their skill and feasibility and

experience. It ensures they have enough knowledge

and awareness about the present study problems. The

coding step identified a big picture of the facts as

qualitative data analysis and collecting and drawing

conclusions on a psychological analysis (Mahpur,

2017). The results from coding will be analysed

related to the development of 4G network

optimization based on smartphone penetration.

After collecting data and conducting interviews,

the recording in audio form then converted into

writing and in text form known as Verbatim

transcript. Verbatim transcripts are grouped into each

No MSISDN Device Type USIM Device

1 6285215495560 Smartphone Y 4G

2 6285254815373 Featurephone N Others

3 6281380475456 Smartphone Y 4G

4 6281311221371 Featurephone N 2G

5 6281311242788 Smartphone Y 4G

6 628128348786 Smartphone Y 4G

7 6281387878899 Smartphone Y 4G

8 628129504899 Smartphone Y 4G

9 6281318421564 Smartphone Y 4G

10 628128019990 Smartphone Y 4G

11 6281314207888 Featurephone N 2G

12 6281384915158 Smartphone N 4G

13 628129985695 Smartphone Y 3G

14 6281394866009 Smartphone Y 4G

…… 628128913026 Smartphone Y 4G

40000 628128908082 Smartphone Y 4G

Optimization Strategy of Mobile Cellular Network based on Customer Smartphone Penetration

501

variable according to the questions asked. The results

of the complete. Then each verbatim transcript data

will undergo a reduction process, where data is

important and directly related to the research which is

the main note to take a conclusion. Coding for

Expertise using I, and for Customer using II.

4.2.1 Compatibility

Compatibility is used to measure the suitability of 3G

device usage is associated with the need to access of

internet. Some respondents answered questions as

follows:

The device has 4G capability but it’s not a 4G USIM

card, because I felt too lazy to go to Graphari office,

another reason caused by wasteful battery handset (II

.1).

The device has 4G capability but it’s not a USIM card

because welds queue to Graphari office (II.2)

The device is still 3G, including the sim card, it is

sufficient with 3G (II.3)

Using 3G device with sufficient speed for internet

connection. (II.4)

Lack of understanding the 4G technology, using 3G

is enough for internet connection. (II.5)

From the customer side, the reason is not to

replace the 4G handset, because of 3G technology

services are sufficient, so they do not need to

exchange 4G services. The use of internet data

activity for social media is sufficient even if only

using 3G handsets. For customers who already used

4G handsets, but have not replaced the sim card with

4G USIM. The reasons as revealed by resource

persons II.1 and II.2 is the reluctance to queue

graphically when changing cards and there is a view

that by using 4G wasteful quota.

This is in accordance with what was stated by the

Expertise 1 (I.1) that replacing the 4G USIM card is

more of a challenge:

For me, the more challenging is customer want to

change the sim card, this is different from the others,

if it used to be 2G, 3G people don’t need to change

the sim card, but in 4G, people have to change sim

card. (I.1).

More clearly explained by the Expertise 2 (II.2),

the factors that affect customers who have not

replaced the 4G USIM are:

Well, usually, they don’t want to change 4G devices

due to some aspects, there is a perception that using

4G data has a fast impact on the internet quota and

the battery. (I.2).

This shows that the matching between the answers

presented by the customer is not different from the

experience found by experts. There is a view that

using 4G technology causes fast quota spending and

handset battery is the main reason, aside from that

customers feel enough to use 3G technology services.

Besides the reluctance of customers to replace the 4G

USIM card through a service at Telkomsel office.

4.2.2 Observability

To find out that customers have observed 4G

technology, both 4G device usage and information

related to 4G technology. The advantages of 4G

technology are compared with 3G technology. The

answers from the respondents are as follows:

Ever observed, the information is faster to access the

data (II.1)

Ever observed and tried it. (II.2)

Ever watched (II.3)

All participants claimed to have observed 4G

devices. While technology has heard and learned

about the advantages of 4G technology compared to

3G technology. This shows that the introduction of

4G technology has been well obtained by customers,

both in the from corporate and information from the

media. Customers have socialized the capabilities of

4G technology and devices. Various offers made by

4G device providers at relatively low prices make

customers observe 4G device capabilities. While

cellular operators are intensively developing 4G

networks to the regions.

4.2.3 Trialability

After making observations, in general a participant

will try on the known technology. Trialability is to

ensure that participants feel the need to change the

device. The answers from the respondents are as

follows:

I have tried it, and the data rate is more accessible.

(II.1)

I have tried and compared with the 4G device. (II.2)

Never before, because I don’t need it yet. (II.3)

I once used a husband’s 4G device. (II.4)

So far, I have never tried it. (II.5)

ICIB 2019 - The 2nd International Conference on Inclusive Business in the Changing World

502

Most participants have tried with 4G devices. This

shows that there is a desire from customers to know

more about 4G devices, after making observations in

the previous stage. The presence of 4G technology in

Indonesia since 2016 has been well known by

customers, so they tried the reliability of this 4G

technology. Although their needs have not yet been

desired, they are enjoying the 3G technology that has

been used so far.

IDT theory has compatibility, observability and

trialability variables are more important to see device

penetration from the customer side. This is because to

measure the level of satisfaction and experience of

customers towards both 3G and 4G technology.

While TAM is a continuation of IDT to measure the

company to find out the cause of 4G device

penetration is still low. As well as strategies that will

be carried out by companies to deal with these

problems.

4.2.4 Perceived Useful

In the variable perceived useful not only from the

customer side but from the problems faced by the

company related to 4G device penetration. As

contained in secondary data presented at the

beginning of the study, national penetration of 4G

Telkomsel handsets up to July 2017 still reaches 42%.

While for the Jakarta region based on sampling data

on 40 thousand customers, the penetration reached

57%, and 38% used USIM cards.

Based on the interview, the responses from the

participants were:

“So, if we go back to the problem, maybe it’s the

fundamentals because we don’t subsidize so we

submit to the market mechanism, so the number of the

penetration may not be as much as countries that

apply mobile subsidies.” (I.1)

Actually, Telkomsel for 4G penetration is very closely

related to partnerships carried out by Telkomsel

itself. This means that Telkomsel is not a device

provider, whether we want it or not, we must

cooperate with the partnership parties. (I.2)

The results show that the factors that caused the

low penetration of 4G Telkomsel handsets are

because Telkomsel did not subsidize customers’

handset. Telkomsel depends on market mechanisms,

the bundling program is more in collaboration with

partners and Telkomsel provides products and the sim

card. In addition, the availability of handsets in the

market and the distribution of handsets between

regions varies. Partnership partners will certainly

count by looking for markets in regions that will

absorb 4G handset purchases. Not all 4G handsets

will be provided by partnership partners. This is

especially true in rural areas where the economic rank

is lower compared to urban or suburban areas.

Based on the chart of 4G Telkomsel handsets, it

appears that since the beginning of the 4G service

Telkomsel was launched (December 2014) has

increased, especially in 2017 until mid-2018, but after

that there has been a slowing down and approaching

saturation. From the results of interviews with the

respondent saying that:

“I don’t know what to do with the sim card

registration, maybe, I don’t know that, but if you see

the timings like having a straight line with the sim

card registration, because after that April there is a

sim card registration (I.1)

This data in my opinion there are actually two sides,

first, is the economy really turbulent, it could be that

he will buy purchases for the handset, because our

new IMEI is also small, that’s one. (I.2)

There is a connection between the registration sim

card conducted by Regulator with the slow

penetration of 4G Telkomsel handsets, because the

NIK and NOK (identity number) based registration

process has made customers stay more with their old

handsets and not replace new cards. In addition, the

tendency of customers to hold back in replacing new

handsets is the reason for the penetration of 4G

handsets to slow down.

Researchers predict that the growth of 4G devices

in the future will not increase dramatically as in the

previous period, there will be an increase along with

the increasing coverage network built by Telkomsel,

although not as large as the period before April 2018.

As in life cycle technology theory, this phase is

approaching maturity stage, flat growth and

approaching deceleration. With the number of 4G

handsets approaching 70 million, the predictions of

penetration researchers will reach a maximum level

of 90 million. This is inseparable from the factors

revealed by the experts above. The tendency of

customers not to buy a new handset and feel sufficient

with the condition of the handset that is now owned

is the biggest factor that influences it.

4.2.5 Perceived Ease to Use

Furthermore, it relates to the ease and strategies for

improving 4G device and USIM card usage,

participants explained that:

Optimization Strategy of Mobile Cellular Network based on Customer Smartphone Penetration

503

Efforts that have been made by Telkomsel in

increasing the penetration of the 4G USIM include

distribution of all the initial cards using USIM,

mapping sites for customers other than 4G, campaign

through CTP (customer touch points) and dealer

partners and outbound calls for customers with high

ARPU. As stated by the resource person (II.2)

“First, for the product side, all of the first distribution

now, have started using all of us, that’s already from

2017 or 2016, all of them have begun to work.” (II.2)

“Well, if the programs have been done, first it will

map to those areas, the points where per site, per site

where there are still a lot of sim cards, at any point,

we make the first priority.” (II.3)

“The campaign to migrate to 4G at the point of our

CTP, then we are also cooperating with AD

(authorize dealer) partners, TDC (Telkomsel

Distribution Channel), then we have More.” (II.3)

The strategy is carried out with campaign and

awareness for customers to increase device

penetration and 4G sim card in various ways (II.4).

Efforts made by Telkomsel to facilitate customers

in obtaining services for customers and increase 4G

device penetration. Various ways are started from

awareness, contacting customers directly,

cooperating with Telkomsel partners, and offering

additional products for customers. Besides the

provision of 4G networks that have reached the area

by Telkomsel to make it easier for customers to

communicate with 4G technology.

5 CONCLUSIONS

This paper combines the concept of IDT (i.e.

compatibility, observability and trialability variables

and TAM (i.e. perceived variables is useful and

perceived ease to use). These two theories are used to

explore the relationship between customer experience

also the presence of 4G technology and 4G

technology provided by telecommunications

operators. By knowing this, the telco operators will

have the right strategy in overcoming the problem.

From the data, we can conclude that the

compatibility variable in IDT’s theory plays a vital

role compared with observability and trialability

variables. It seems that compatibility does not

accordance with customer needs for the presence of

new technologies, even though new technologies

represent service excellence. While the observability

and trialability are only support to find out the

reliability of the new technology. Even though, in the

end customer needs become the top priority. There is

a very close relationship between the variables in IDT

and TAM's theory in influencing customer decisions

in adopting new technologies.

The customer’s opinion is using 4G devices

wasteful in both their quota and handset battery, and

customers already feel sufficient with the speed of 3G

network data access. For customers who use 4G

devices but have not replaced the 4G USIM card due

to the reluctance to wait a long time when visiting

Ghrapari Telkomsel Office.

Strategies for increasing 4G USIM penetration

include the initial distribution of all cards using

USIM, mapping sites for customers other than 4G,

campaign through CTP (customer touch points) and

dealer partners and outbound calls for customers with

high ARPU. The development of 4G networks

continues to be achieved equilibrium with regions

that require an increase in 4G network coverage, more

selective development for regions that need 4G

services.

REFERENCES

Annual report Telkomsel, 2017. https://www.telkomsel.

com/about-us/investor relations. Accessed 20 January

2019.

Annual report Indosat Ooredo, 2017. https://www.indosat

oredoo.com/id/investor-relation/informasi-keuangan

/laporan-keuangan. Accessed 20 January 2019.

Annual report XL (2017). https://www.xl.co.id/id/about-

us/investor-room/financial-statement. Accessed 20

January 2019.

Ajzen, I., 1991. The Theory of Planned Behaviour.

Organizational Behaviour and Human Decision

Process [Online]. Available: http://www.courses.

umass.edu/psy661/pdf/tpb.obhdp.pdf [2009, February

25].

Davis, F., D., 1986. A Technology Acceptance Model for

Empirically Testing New End-User Information

Systems: Theory and Results (Doctoral Dissertation,

Massachusetts Institute of Technology, 1986).

Indrawati., 2017. Perilaku Konsumen Individu dalam

Mengadopsi Layanan Berbasis Teknologi Komunikasi

dan Informasi. Bandung: Refika Aditama

L. Chen, M., L., Gillenson, and D., L., Sherrell., 2002.

Enticing online consumes: An extended acceptance

perspective. Information & Management, 39 (0), pp.

705-719.

S. Oh., J., Ahn,, and B., Kim., 2003. Adoption of broadband

Internet in Korea: The role of experience in building

attitudes. Journal of Information Technology, 18(4), pp.

267-280.

ICIB 2019 - The 2nd International Conference on Inclusive Business in the Changing World

504

J. H. Wu and S., C., Wang., 2005. What drives mobile

Commerce? An empirical evaluation of the revised

technology acceptance model. Information &

Management, 42(5), pp. 719-729.

J. Min, Y. Noh., Ghee., 2018. Combined Model of

Technology Acceptance and Innovation Diffusion

Theory for Adoption of Smartwatch. International

Journal of Contents, 14(3).

Mahpur, M., 2017. Memantapkan Analisis Data Kualitatif

Melalui Tahapan Koding. Malang: PT Anugrah

Miles, M., B., Huberman, A., M., and Saldana, J. (2014).

Qualitative Data Analysis. A Methods Sourcebook,

Edition 3. USA: Sage Publications. Terjemahan Tjetjep

Rohindi, UI-Press.

Rogers, E.M., 2003. Diffusion of innovations (5

ed.). New

York: Free Press.

Sahin, I., 2006. Detailed review of Roger’s diffusion of

innovations theory and educational technology-related

studies based on Roger’s theory. The Turkish Online

Journal of Educational Technology (5) 2, 14-23.

Sugiyono, 2014. Metode Penelitian Pendidikan

Pendekatan Kuantitatif, Kualitatif dan R&D. Bandung:

Alfabeta.

Zikmund, W., G., Babin, B. J., Carr, J., C., & Graffin, M.,

2010. Business Research Methods, Eighth Edition.

Cengage Learning: Singapore

Optimization Strategy of Mobile Cellular Network based on Customer Smartphone Penetration

505